for People with a Passion for Period Property
Ask an Agony Uncle!
Stephen Boniface - Stephen Boniface specialises in building conservation providing multi-disciplinary consulting services. He is Chairman of the Building Surveying Faculty and member of the Residential faculty. He serves on the RICS Building Conservation Forum Board and is the 'Agony Uncle' on the Period Property UK website (

Ask our Agony Uncles ...

You can write to our panel of experts free of charge on any subject, providing it's got something to do with Period Properties.

Our experts are all specialists in matters directly involved with older properties. So, if you have a problem with an older building - or if you think you might have a problem - ask an Agony Uncle...

o Restoring a packed earth floor Caroline Payne (Surrey)
o Ten year old damp Cathy Smith (Hertfordshire)
o Can we avoid a chemical injection? Gill Korszanski (Dumfries and Galloway)
o Chimney liners - stainless steel or in-site cast concrete? Richard Buller (Northamptonshire)
o Pesky sparrows Robert Woolf (Cambridgeshire)
o Our Victorian house is cold and draughty Jenny Steadman (Cheshire)
o After the fire... Anonymous (Cheshire)
o 'Clinker' built house Nadine Cordell (Hertfordshire)
o Who owns that derelict property? Lindsey Wale (West Glamorgan)
o Confused by damp specialists Lyn Taylor (Essex)
o Tank damp Ms. Neilson (Greater London)
o Putting back a staircase Paul Nurton (Essex)
o How to shave a cow Adrian Rudd (Derbyshire)
o How can we convince the Building Control Officer? Jenny Bishop (Essex)
o Our sandstone has turned to sand Ruth Aldis (East Sussex)
o Are wooden beams in our chimney a fire hazard? Emma Hawkins (Hampshire)

SUBJECT: Restoring a packed earth floor
FROM: Caroline Payne (Surrey)
Do you know how one would go about restoring a packed earth floor? Presumably it's more complicated than putting down more earth and stamping on it?!

And how does it fare in the winter?

The floor is currently badly pitted and has had a very thin layer of green growth over it at times. (The roof of the building has holes in it and the front door has disintegrated - so presumably the floor has got wetter than it's meant to be).

Fifteen years ago it was smooth and soft and dry and amazing (I never saw it during the winter months) but if I were to purchase it, I would love to restore it somehow.

Caroline Payne

I note that you also posted this on the discussion forum. I think the basic answer is that an earth floor is best restored using a mix including earth, sand and lime. To compact it, you could simply tamp it down. It might be possible to hire and use a 'wacker' plate or simply use something like a heavy garden roller if you have the space.

The other issue here though is that it seems to be getting wet. I think this is a matter you need to think about carefully. Have there been any changes around the building, in the vicinity, etc that might have resulted in an increase in groundwater, or water laying around the building, etc?

I suspect you may have to think about putting in a French drain, or similar, in an attempt to ensure that water is 'caught' before it gets to the house and directed away. This should then reduce the amount of groundwater under and around the base of the property. In turn this should help ensure that the floor remains relatively dry.

Without seeing the property it is difficult to advise specifically. When I read your question I wondered if a French drain in the form of a proper land drain would be of benefit. This would involve excavating a trench around the building (or part) ensuring that it drains away from the building, preferably into a soakaway, etc. You would need to lay a geotextile membrane and then a land drain (perforated drain) and then back fill with shingle. This is a very brief description and there have been discussion on the Forum and links to other sites that might help you better on the matter of a French Drain. The one thing to remember if putting in such a drain - ensure that you create a couple of access points. Even with a geotextile membrane there is a risk of it silting up and the access points help ensure you can clear it.

Period Property UK would like to thank Stephen Boniface, Tony Redman and other partners at the The Whitworth Co-Partnership with Boniface Associates for responding to this question.



SUBJECT: Ten year old damp
FROM: Cathy Smith (Hertfordshire)
We have a 150 year-old chalk clunch property where the chalk walls (which are generally in good condition) rest on brick foundations. The outside of the property is rendered, with the render finishing about a foot above the ground level. The bricks have had a chemical d.p.c in the past. However, one wall - the most exposed one - is timber frame from about 18 inches up and brick below. The brick is damp and appears in a bad state where it is visible under a door sill. There is a plastic physical damp barrier that seems effective in stopping damp rise to the timbers. But we have continuous modern plaster inside the house which is slightly damp up to that barrier and especially at floor level. The damp also extends round the corners to the brick under the clunch walls.

We also have modern render on the outside of the wall (except where the door is), that goes right down to the ground, expanding out to cover what is presumably a slightly thicker foundation at ground level. I know that this cannot be good for the bricks as they can't breathe, but our builder (not a conservation specialist) told us that they needed that protection.

I have fairly happily lived with the damp for 10 years but I would like to do the best for the building. If we get the outside render taken off, will the brick foundations suffer? Might they have to be replaced? Can we replace the inside plaster with something more breathable?

Cathy Smith

It sounds like your problems need an inspection, but let us see how far we can get here.

Now that a chemical DPC has been inserted it is irreversible and we have to work around this. The solutions therefore may not be what would be used if there were no DPC injected.

I suspect the deteriorating bricks below the DPC, or at low level, are due to the fact that instead of damp being unrestricted and evaporating wherever it can, it is now contained below the injected DPC. This means that the low level bricks are having to deal with more moisture than previously and this could be a reason for their failure. I can only suggest that when replacing these bricks you use a brick type that matches in colour, etc as closely as possible, but that is more resilient to moisture (particularly frost).

You do not say what type of render you have. The fact that the base of the wall is exposed and not rendered should help ensure that low level moisture can escape before rising to any point whereby it can cause damage. Nonetheless, if the render is cement based you should have a long term aim to replace it with lime render.

Of course, where the render runs down to ground it should be cut back. If you cannot afford to completely change the render it would be of some benefit if you at least cut back the bottom of the render to a point at least 150mm above ground and preferably higher (the precise height will depend on the circumstances).

In taking off the render you may find that brick faces come with it. You may find that you have to cut out and replace some of the bricks. It is unlikely that removal of the render will cause a structural problem. If the render is on a timber frame and the frame is rotten removal of the render could be problematic, but I don't think that applies to you. Removal of the render from the Clunch could also cause surface damage and care should always be taken. It is often best to undertake a trial area of removal before launching into large areas.

Regarding the internal plaster, I suspect you would be best advised to take off the modern plaster and replace it with lime plaster.

Period Property UK would like to thank Stephen Boniface, Tony Redman and other partners at the The Whitworth Co-Partnership with Boniface Associates for responding to this question.


SUBJECT: Can we avoid a chemical injection?
FROM: Gill Korszanski (Dumfries and Galloway)
We are converting a steading to a dwelling. Single storey and built with a mix of sandstone, flint etc which is some 18inches thick. We have been advised by the building standards chap that we are required to have a damp proof course. He suggests chemical injection. From my investigations this does not appear to be a good idea and it appears may do more harm than good. He is happy for us to state that there is an existing slate course. We are unsure how to locate this if it exists. The building used to house a mill wheel although the stream has been redirected away from the building. There is no sign of any damp in the building. We will be building stud walls of the inside masonry with the required vapour shields insulation etc, and a membrane on the floor which is a very deep concrete slab, also dry. I would be grateful for your advice and how we can persuade the building standards that his idea is not a good one.

Gill Korszanski

It is certainly not a good idea. With sandstone what you will probably find is that above the DPC the Sandstone will be OK, but below it will degrade and fail quite quickly due to the increased moisture in a restricted zone.

There is nothing in the Building Regulations that 'require' a DPC. The creation of an internal drained cavity type of system to ensure that you have dry internal surfaces sounds perfectly reasonable and acceptable. This would allow the walls and floor to function as before but with dry internal surfaces for occupants.

Unfortunately, there is no easy way to persuade the Officer involved. You could point him to this site (bearing in mind that Council Officers are regular posters on the Discussion Forum), or print off appropriate extracts and hand them to him. You could find an independent 'Approved Building Inspector' to fight your corner, or you could get an Architect or Surveyor experienced in historic buildings to argue your case.

With regard to how to find a slate DPC, it depends, but if it exists it will be one or two layers of slate laid horizontally towards the base of the wall. Only the edge of the slate will be seen. In a stone wall it may be possible to see because it will form a straight horizontal line. If the stone is rubble laid, the DPC may be the only straight line! However, I doubt there is a DPC in the wall.

Period Property UK would like to thank Stephen Boniface, Tony Redman and other partners at the The Whitworth Co-Partnership with Boniface Associates for responding to this question.



SUBJECT: Chimney liners - Stainless steel or in-site cast concrete?
FROM: Richard Buller (Northamptonshire)

I have been advised by the chimney sweep to line the chimney of my two storey stone cottage built in approx 1630. I currently have a Clear View stove and burn mostly wood. I have requested quotes for a stainless steel liner and an in-site cast concrete liner.

What are the relative merits of both systems and which will be best in my particular case?

Richard Buller

The smoke from a wood burner contains many materials including a few nasty chemicals. These can have a corrosive effect on a number of materials. Most wood burners I see have been fitted with a stainless steel flexible liner. It is accepted that this might need replacing in future, but that is something an owner will budget for.

The advantage of a steel liner is that it is relatively cheap, quick to fit and it is reversible. The disadvantage is that it will need to be replaced, perhaps within 10-20 years.

In situ concrete, once installed, is permanent and cannot then be removed. It is far more resistant to the smoke and does not degrade so easily. However, it takes longer to fit and once in can never be removed (without taking the chimney down!). Another problem with older properties is that there have been a few occasions (rare) where the pressure of the concrete going in caused the chimney to fail (the concrete pushed it apart).

My preference would be for the stainless steel liner as it is not permanent and there is no risk to the chimney.

Period Property UK would like to thank Stephen Boniface, Tony Redman and other partners at the The Whitworth Co-Partnership with Boniface Associates for responding to this question.



SUBJECT: Pesky sparrows
FROM: Robert Woolf (Cambridgeshire)
Sparrows appear to have taken a liking to our flint walls to the point where they have pecked the lime mortar away so much that flints are falling free. Do you have any suggestions how I can deter them please - and what are they getting from it?

Robert Woolf

I have heard of this before and from recollection I think it is the calcium they are going for.

You cannot change to a different mortar (e.g. cement based) because that could cause you long term problems. You therefore have to repair the damaged lime mortar with lime and then find a way to discourage the birds. I can only suggest you find advice on bird scarers. I suppose you could hang a fine mesh just beyond the face of the wall so that the appearance remains, but the birds cannot reach the wall. The drawback with this is that the birds might get entangled in the mesh. I suggest you speak with RSPB to see if they have any ideas on how to deter the birds. I suspect that once you have stopped them for one or two years they will give up and go elsewhere, but I may be wrong and this is where RSPB are the best people to speak with.

Period Property UK would like to thank Stephen Boniface, Tony Redman and other partners at the The Whitworth Co-Partnership with Boniface Associates for responding to this question.



SUBJECT: Our Victorian house is cold and draughty
FROM: Jenny Steadman (Cheshire)
We have a detached Victorian property and in the winter it is extremely cold and draughty! This is mainly due to the original wooden windows and door (which we are unwilling to change as it will affect the character of the house), but we also feel that we are probably still losing heat through the loft. (We have insulated the loft between the joists in both directions to the current recommended depths), have a new boiler and room temperature radiator controls, and also try to keep doors etc closed during the winter months. Our heating bills are continually high and every winter we are still very cold!!!! My husband feels that heat must still be being lost out of the roof and we are considering having the house re-roofed and felt and insulation added behind the tiles for insulation. (The clay tiles are currently straight onto the slats).

As we already have insulation between the joists in the loft I'm not convinced that this will make much difference!

Jenny Steadman

As heat rises the roof is the place to start when considering insulation. I would not advise re-roofing just to put in a lining and insulation to the slopes. This simply means that you will be heating your loft space in future!

The best place for insulation in a roof is over the ceilings. It sounds as if you have done your best with this. Make sure it is at least 200mm thick in total. Make sure it covers the whole area and ensure that the loft hatch itself is insulated and with draught-proofing to the edges of the hatch. As the roof is not lined at present there should be sufficient natural ventilation and you should not have to specifically ventilate the roof space.

The next element to consider is the wall structure. I suspect there is little you can do about the walls, but check to make sure that the main areas are of a solid wall construction at least 9-inches thick (225mm). If any are thinner than this it may indicate a half-brick wall. If this is the case you may want to consider a form of insulated dry lining on the internal face. This would involve quite a lot of work and may mean internal changes in the room/s in question. If the building is listed you would need to get listed building consent.

Next are the windows and doors. There is much debate about the issue of single versus double glazing, but as a simple guide - if your existing windows are sound then it is not environmentally sustainable or desirable in any way to replace them simply to install double glazing. If a window or door needs to be replaced the issue of whether to install a double glazed unit then arises. However, I would point out that even with double glazing if there are draughts the benefits will not be so great. I therefore believe that sorting out draughts can be as effective as anything else. Check to ensure that you have a good draught-proofing system to doors and windows.

Secondary glazing is often a suitable solution to such problems. If carefully designed to merge in with the existing windows, it need not be too obvious. It provides the 'double' glazing and in fact the bigger gap is better for sound insulation. In summer it can be removed if necessary.

Another simple solution is to use shutters (if they are fitted to windows) and/or hang heavy curtains.

Have you fireplaces? If so these could be drawing cold air through the building. Consider having a 'chimney balloon' inserted when the fireplace is not in use. Where a fire is in use you could have an air vent in the floor close to the fireplace so that the air is being drawn from the floor void, rather than through the whole house.

As for the boiler, radiator controls, etc these merely control the heat you put in. By the sounds of it you do not need to be so concerned about the heat going in, but sorting out the heat loss. You can simply turn up the heating to very high levels and although much will be lost the residual heat will be sufficient for your comfort. This would be expensive and not environmentally friendly. By improving insulation in sensible ways, you should be able to cut down on your heat loss, which is better for your pocket and the environment.

A couple of other points. The positioning of radiators can have an effect on the efficiency of the heating. You could have a heating engineer look at this and advise.

Keep the whole house heated and do not close off rooms. The whole building will then feel warmer and the boiler is not having to do so much work when a cold room is suddenly opened (which will itself create draughts). By closing off a room and turning off the radiator in that room you are effectively bringing the outside cold walls in to the building. You can use radiator thermostats to turn down the level of heat in unused rooms, but do not turn them off completely.

I hope these pointers help.

Period Property UK would like to thank Stephen Boniface, Tony Redman and other partners at the The Whitworth Co-Partnership with Boniface Associates for responding to this question.


SUBJECT: After the fire...
FROM: Anonymous (Cheshire)
We live in a Grade II thatched cottage built c.1750. We bought it after it had been rebuilt following a chimney fire. I have two queries:

Following a fire what process would our vendor have needed to have gone through with the local planning office prior to rebuilding the property? In the attic space there is evidence of breeze block having been used for the exterior walls which then have Cheshire brick as the "outside" wall. I would like to know whether this would comply with a planning office's guidelines. If our vendor did not rebuild according to the guidelines required where do we stand legally?

Secondly, we would like to install a stove into a fireplace. What issues do I have to consider to ensure that we do not put our family and lovely thatched roof at risk?


It really depends on how extensive the fire was and what rebuilding, etc took place. I would normally expect the Conservation Officer to have had some input and perhaps the Building Control officer as well.

If the work was simply to reinstate what existed previously there may not have been a need for listed building consent.

There are no guidelines as such, other than the general guides published in PPG15 (Planning Policy Guidance 15). This does not actually tell you what you can and cannot do as such, because each situation has to be considered on its merits.

I have seen rebuilt historic buildings where it was agreed between all parties to reconstruct using modern techniques (i.e. cavity walls) but ensuring that the outer leaf was in an appropriate brick and bonded to look like solid brickwork. This is an approach often used for extensions to historic buildings.

The information you give is insufficient to say whether you really have a problem or not. If you have not purchased then when your solicitor undertakes local searches get him/her to ask specifically about the reinstatement works. If you have already purchased what showed up in the searches? Go and ask to see the planning file (and as an owner you should be able to get access to the Building Control file as well). They do not need to know why you want to look at it.

Check first in case there is a note to the effect that the work did not need consent in the opinion of the officers at the time. If you find that the work was undertaken without appropriate consents as you did not undertake the work the Council would not prosecute you (or at least would find it very difficult). The worst they could do is make you rebuild in a different way. However, if the original wall was lost in a fire the original materials cannot be used and therefore any replacement is simply a replica. Provided the external appearance is acceptable they may take the view that the method of construction, in this instance, was not a major issue.

In my view I suspect you are rather over sensitive about legal repercussions, but you do need to satisfy yourself that the work was acceptable and that you will not face enforcement action to rebuild the wall in question. You can only do this by looking at the Council files and perhaps talking with the Conservation Officer.

As for future use of the chimney the simple answer is that it must be lined.

At roof level the top of the pot/chimney should be at least 1.8m above the nearest thatch. If it is not you may have to extend it (for which listed building consent would be needed). I personally do not like spark arrestors, as they require regular cleaning and to get to them often damages the thatch.

Most thatch fires are because of heat and/or sparks through the chimney (not out of the top) and you should check to ensure that the reinstatement after the fire include repointing, etc.

Regarding the lining, this should be full height and I suggest it be insulated to reduce the likelihood of heat transference through the brickwork to the thatch.

These measures should reduce the risks.

I would point out that fires in thatch are actually very rare, but when they do happen they can result in quite a lot of damage.

Period Property UK would like to thank Stephen Boniface, Tony Redman and other partners at the The Whitworth Co-Partnership with Boniface Associates for responding to this question.


SUBJECT: 'Clinker' built house
FROM: Nadine Cordell (Hertfordshire)
We are in the process of trying to buy a 1920's semi-detached house in Hertfordshire that has been built out of concrete blocks. Apparently the blocks are called 'clinker'. A neighbour has advised that some mortgage companies do not lend on this type of construction and that we will need to get an engineers report to clarify whether the concrete is failing. We are not purchasing this property with the aid of a mortgage, but my worry is when we come to sell the property on.

There are a few other houses in the area constructed out of the same material and all seem solid with no evidence of failing and some have mortgages on them.

Please can you tell us whether this is really is a problem and if so, please let us know the name and telephone number of an engineer who can carry out a survey of the concrete.

Nadine Cordell

Many houses were built using clinker blocks in the 1920s and 1930s. It is true that some mortgage lenders do not like lending on such properties, but then mortgage companies can pick and choose what they lend on at any time (some change their rules periodically). There will be mortgage companies that will lend on them and if you talk to enough of your neighbours I suspect you will find that they have mortgages through various companies, probably including some of the better known lenders. When you come to sell you simply need to ensure that purchasers are aware that some lenders would not lend on it, but others would - have a list of those who will and give it to the Agent.

Bear in mind also that if you sell after January 2007 the rules will be different and every house sold will have a Home Information Pack, thus lessening the risk of problems over the construction, etc arising late in the transaction.

All buildings deteriorate with age, but the rate of deterioration depends on the nature of construction, materials used, how the building is maintained over the years, etc, etc, etc.

From recollection houses built with clinker blocks are not regarded as inherently defective.

A problem you may encounter if it has cavity walls is that the cavity ties may be prone to failure due to the chemical reaction between materials in the clinker blocks and the ties, as well as the ties failing (rusting) anyway. However, cavity tie failure is not a problem isolated to houses built of clinker blocks, but is a problem that can affect cavity walls of many types built until the mid 1980s.

As for professional advice I suggest you speak to some local Building Surveyors and/or Engineers who work in the vicinity and are used to inspecting these properties. They will be able to tell you about known problems, if any. The RICS web site has a section for the public on finding a surveyor in your area.

Period Property UK would like to thank Stephen Boniface, Tony Redman and other partners at the The Whitworth Co-Partnership with Boniface Associates for responding to this question.


SUBJECT: Who owns that derelict property?
FROM: Lindsey Wale (West Glamorgan)
I am trying to find out who owns a derelict property. I have checked with the land registry, and it's not registered. The person who lived there died about 7 years ago, and the property was left to the owners brother, who has since died. I don't know who the brother was - the only evidence I have is anecdotal, one of the neighbours thinks his name might have been Mr Jones! What would my next step be?

Lindsey Wale

Not an easy one and it is rare that I have had to find owners.

If you know the name of the original owner go back to birth and death records to find his details and thereby his brother's name. You may then be able to find out if the brother left a will or died intestate. There would have been probate when the brother died and you should be able to trace records of this. From this you may be able to find who now owns the property. If he died intestate and there is no inheritor, I assume the property was part of his estate and is now 'owned' by the government?

Look in the property to see if the post is being collected or cleared by someone. If so, leave a letter on the door or where that person can find it when they next visit.

Post ads in local and national newspapers asking for the owner to contact you.

Finally, you could take possession and see what happens! :-)

Period Property UK would like to thank Stephen Boniface, Tony Redman and other partners at the The Whitworth Co-Partnership with Boniface Associates for responding to this question.


SUBJECT: Confused by damp specialists
FROM: Lyn Taylor (Essex)
I have recently purchased a property - built in 1550. There is extensive damp throughout the ground floor - which was highlighted by my surveyor and was always something we knew we would have to deal with. I have obtained quotes from a number of builders/DPC specialists and I'm more confused than ever! The prices vary from under 2,000 to over 10,000 - some say that the kitchen (which has damp on all walls) needs to be taken out and others say it's not necessary. I've had the local historic buildings advisor visit the property who told me that a DPC may not be necessary! I am sympathetic to maintaining the historic elements of the building, but I'm not prepared to live in medieval conditions!

Lyn Taylor

This is not the first time in the past month when someone has suggested to me that by allowing a building to function properly it means automatically that they have to live in "medieval conditions".

The historic buildings advisor is quite correct and you must let the building function properly. Application of modern damp proofing, etc is likely to cause a significant increase in the decay of the materials and you will simply accelerate the deterioration of the building. This is not in your interest and not in the interest of anyone who cares for historic buildings. Let us therefore ignore the advice to inject walls, etc, etc.

Start by finding out what is really going on with the property. It is of course possible that there is a serious damp problem. This may be caused by past attempts to 'cure' damp and the imposition of modern materials. It may be caused by changes that mean the building no longer functions as it once did. You may have to consider undoing past works, if inappropriate, or changing things to allow the building to function properly (e.g. lower ground levels if high, unblock air vents if covered, etc, etc).

In doing all this remember that the damp may be a surface problem. If the building is timber framed, what condition is the frame in behind the damp surfaces? Going around injecting the walls will not cure rotting frame members. Indeed application of modern materials, etc could make the problem worse in a fairly short time span.

What level of survey did you have? Ask the surveyor to advise properly, but if he/she is not experienced with historic buildings then find someone who is. Bear in mind that if you have already purchased and the original surveyor did not do the job properly and you find yourself with more problems and work than meets the eye you could have a case for suing the surveyor for negligence (even though the damp was mentioned).

As for living in the past - I suggest you read the Discussion Forum. Breathable structures cannot be sealed up without serious consequences and therefore a slightly adjustment to lifestyle may have to be made. For example, on a breathable stone floor you should not install fitted carpets, but there is nothing wrong with having some rugs laid out (lift them regularly to air the floor). You cannot use vinyl wallpaper on lime plastered walls, but what is wrong with limewash, etc (even a lining paper and matt emulsion would not usually cause any harm)? There are many historic buildings functioning properly and yet providing modern levels of comfort. Just because they function differently does not mean that you need to forego modern comfort levels. It sounds to me as if what you really need at present is some sound advice from someone who properly understands historic buildings.

Period Property UK would like to thank Stephen Boniface, Tony Redman and other partners at the The Whitworth Co-Partnership with Boniface Associates for responding to this question.


SUBJECT: Tank damp
FROM: Ms. Neilson (Greater London)
I have recently moved in to an Edwardian basement flat and have had the hallway re-skimmed. The walls (all internal) had been covered in many layers of paper and paint but seemed essentially sound, though there were some small areas where the paper had started to lift from the bottom and the wall underneath appeared dry but with a white powdery residue. On removing the skirting we found out that it was rotten in places as well.

Since replastering a week ago, extensive areas of salt deposits have come up, at a low level. In the worst affected areas, some small areas of new plaster appear to have blown already.

Does this indicate rising damp, in your opinion? My homebuyers survey and the estate agent's free timber and damp survey (yes, both bad ideas with hindsight!) carried out earlier in the year indicated no major problem with damp.

I had my bedroom (on the other side of an affected wall) plastered a few days before and encountered none of these salt damp problems. I'm wondering if it may be down to moisture levels in the air - I used a dehumidifier set at a low level to help dry the plaster out evenly in the bedroom and could keep a window open constantly, but on my plasterer's advice didn't use the dehumidifier in the hallway for a week, to let the plaster dry out more naturally, and can only ventilate the room when I am at home.

I'm aware I probably need to get this surveyed thoroughly, but would like to go into any consultation regarding remedial work with some idea as to the possible causes.

Ms. Neilson

Is this a basement that was converted to habitable accommodation, or was it always habitable rooms?

The former is far more likely.

The evidence you describe could indeed be an indication of some form of damp. However, do not jump to a conclusion on what form of damp and do not assume that this is the type of damp that can be dealt with by some cure-all chemical.

If the basement was converted (as I suspect), it is likely that the walls have been 'tanked'. This is basically a water-proof render applied against the wall surfaces internally intended to hold back ground moisture trying to penetrate through the walls laterally (presumably the basement is fully or partly below ground).

A common problem I come across is where the builders then fix the skirtings with nails or screws straight through the tanking, thereby creating very convenient routes for moisture. What then happens is that moisture gets through these holes and rots the backs of the skirtings where the fixings are and this moisture then starts to travel through the surface plaster, causing it to fail.

What you are suffering now could be the limit of the problem, or the first signs of a more widespread problem. Taking off skirtings that are unaffected may help inform on this matter (if they are all nailed you could face further problems in future).

Tanking systems tend to have a limited life anyway (10-20 years usually), but if punctured problems appear much sooner. To change to a different system would involve much disruption. I therefore suggest you repair what exists. From what you say and if my assumption is correct, I suggest you take off the skirtings and plaster surface skim coat. You should find the render tanking behind and hopefully this will be sound. Clean off the surfaces (brush down and vacuum - don't wash as this will simply dissolve the salts) and plug the holes with a water-proof plug. Using a suitable plaster (i.e. not Gypsum based) re-plaster the surface, but leave a 10mm gap between floor surface and wall plaster. Re-fix the skirtings using a building adhesive.

The above is not a formal Specification, but is a guide as to what might be appropriate.

If I have totally got it wrong with regard to what has taken place in the past, the matter would have to be re-considered.

Whatever the precise construction and detailing of the damp-proofing, it seems that there has been a localised breakdown. You will need to carefully open up to investigate the cause, etc.

Period Property UK would like to thank Stephen Boniface, Tony Redman and other partners at the The Whitworth Co-Partnership with Boniface Associates for responding to this question.


SUBJECT: Putting back a staircase
FROM: Paul Nurton (Essex)
We live in a grade II listed property dating from circa 1500. Whilst renovating the back bedroom we uncovered a doorway in the bedroom wall about six foot above the bedroom floor and which leads to the attic room. There was obviously some form of stairway/ladder at some point in the past in order to gain access to the attic room - however at present we have to make do with a metal loft ladder but would like to reintroduce some form of small wooden staircase. What would be the listed building/building regs implications of putting back what was originally there many years ago. I would very much appreciate receiving any comments or suggestions you may have.

Paul Nurton

As the proposal is to introduce a stair it will have to comply with building regulations. It is quite possible that what previously existed would not comply with modern regulations

If you have the space to install a conventional stair have an architect design and draw it up for you to comply with regulations. You will need to obtain listed building consent as well as building regulation approval. If this is a short flight you may find that some of the regulations (e.g. need for handrails) will not apply.

If you find it difficult to install a conventional stair you could consider what is commonly called a paddle stair. This is used in restricted spaces. There are a number of makes, one of which I came across in a listed building recently and is called the Karina. Do a web search for Spacesaver Stairs and in particular the Karina; there are several suppliers. There are other variations on a similar theme.

If you know a good carpenter you could show the carpenter the spacesaver stair and have something like it purpose made for your space.

For information, a spacesaver or paddle stair is one where each alternating tread has a wider section to one side, for this reason they take up less space. They are usually open tread stairs and riser gap reducers are needed to comply with regulations.

Period Property UK would like to thank Stephen Boniface, Tony Redman and other partners at the The Whitworth Co-Partnership with Boniface Associates for responding to this question.


SUBJECT: How to shave a cow
FROM: Adrian Rudd (Derbyshire)
Is there an alternative to using Lime Mortar, Sand and Cow Hair for torching of a Welsh slate roof? Surely there is a modern substitute? If not do you have a mixing recipe for the above ingredients (and can you tell me how to shave a cow)?

Adrian Rudd

Torching was usually a rough lime mortar applied to the junction between batten and tile/slate.

There are no modern variants. If you perhaps mean the spray-on foam, you should read the Discussion Forum threads to see that it is not regarded as appropriate at all. As it has been discussed at length on the Forum I do not intend to repeat the arguments against its use.

Traditional torching is not difficult. It is possible to purchase ready made mortar and hair for the mix, so that you have to do little other than knock it up and apply it. Much torching I see uses straw instead of hair and this is a variation you could consider.

So put away the razor and start searching the web for suppliers (e.g. Period Property Shop, Mike Wye, etc, etc)

Period Property UK would like to thank Stephen Boniface, Tony Redman and other partners at the The Whitworth Co-Partnership with Boniface Associates for responding to this question.


SUBJECT: How can we convince the Building Control Officer?
FROM: Jenny Bishop (Essex)
We have just purchased a 14C hall house in Essex.

We have concrete floors throughout, which we are removing. We wish to replace the concrete with stone pavers, probably sandstone, laid on limecrete with Leca insulation, with no DPM so it can breathe. (We are currently replacing the soleplates that have rotted due to the concrete). How can we convince the Building Control officer that this is acceptable? Our conservation officer is supportive. Or, is there another alternative?

Jenny Bishop

If the CO is supportive I cannot see the problem. There is much discussion on this site about such floors. The Old House Store has a lot of technical information. I suggest the best thing to do is to print off a lot of the information you can find, especially the technical bits, perhaps include the SPAB stuff on the need for buildings to breathe and any other technical information (extracts from Richard Oxley's book), etc. Then bind neatly and present to the Building Control Officer as your formal technical information on the floor, justifying why it should be allowed.

Period Property UK would like to thank Stephen Boniface, Tony Redman and other partners at the The Whitworth Co-Partnership with Boniface Associates for responding to this question.


SUBJECT: Our sandstone has turned to sand
FROM: Ruth Aldis (East Sussex)
During repointing of small cracks in our external render, our builder discovered the sandstone behind had turned to sand - leaving a gaping hole in the outer skin of the house. Fortunately on this particular wall there is an inner skin built of breezeblock approx. 40 years ago. The house is approx. 400 years old and built of sandstone, timber, wattle & daub. This portion is approx. 250 years old, with a sandstone ground floor, and a timber frame second storey. The house was rendered approx. 40 years ago with a cement render, the second storey being levelled with planks, attached to the timber beams, covered in expanding metal mesh prior to rendering - we assume to give a uniform render. In 1991 the house was damp proofed with a chemical damp course, and at some time, possibly also 40 years ago, the single storey inner wall was built which supports the new ceiling where the staircase used to be. The house has also been underpinned to ground level at some time in the past. We are particularly concerned as this wall supports the upright timbers which in turn support the roof, and there are other areas in the wall that sound hollow under the render - although the render has not come away from the sandstone in any area, and did not fall from the damaged section until the sand had fallen out. We had a full structural survey prior to our purchase in July 2004 and, although the surveyor commented on this crack, he said it was not structural and was merely the result of render stress from covering different building materials, and did not comment on the fact that the wall sounded hollow when tapped. Our insurance company are flummoxed by this and say they have never seen this happen to sandstone before, although I have found an article about Edinburgh houses with crumbling sandstone, although they are much newer. My questions are 1) have you ever heard of this before, and do you know what could have caused it and how widespread or localised the damage is likely to be? and 2) should our surveyor have picked this up at the time of the report?

Ruth Aldis

This is a salutary tale of why cement render should never be used on historic buildings!

To answer your questions:

1) No, it is not something I have come across. I have surveyed buildings in Scotland and noted the severe degradation of sandstone when subjected to cement pointing. From this it follows that a cement render would indeed cause this sort of damage. I suggest you take photos and contact Historic Scotland, because they may well wish to use this as a case study for why cement render should not be used. As for how widespread, I cannot say. It is likely that the ground floor areas will have taken the brunt of the damage, but you may find that quite extensive rebuilding of the whole wall will be necessary. You mention just one wall, are others rendered? If so, you may face similar problems to other elevations in due course. However, only tackle one manageable area at a time - do not over-stretch yourself financially, practically, or emotionally!

2) Not the specific damage, because it was hidden behind the render and other surfaces (and surveyors do not have x-ray vision!). However, the potential problems brought about by using cement on such a building should have been mentioned. I would expect a surveyor knowing anything about historic buildings to have advised that the render was inappropriate, could be causing damage and to anticipate more than simple surface repair. The past works of underpinning and building the internal block wall could all be a result of the sandstone breaking down. Whilst a surveyor may not have been able to say precisely what was going on, the superficial evidence would seem to indicate that there was a hidden problem. In view of this you might have some come-back on the surveyor.

Period Property UK would like to thank Stephen Boniface, Tony Redman and other partners at the The Whitworth Co-Partnership with Boniface Associates for responding to this question.


SUBJECT: Are wooden beams in our chimney a fire hazard?
FROM: Emma Hawkins (Hampshire)
We have a large inglenook fireplace which we use frequently. Having just had it swept, the chimney sweep discovered two wooden beams about a third of the way up which we think may have been use for smoking as they are to the right hand side away from the direct flame of the fire. He suggested that we don't use the fireplace because of the fire hazard. We don't want to install a wood burning stove as suggested and wonder whether we can simply remove the beams. Do you have any advice? The house is 17th century and thatched.

Emma Hawkins

Arguably, as it has survived this long without a fire there should be no problem, but I personally would not want to take the risk. Although thatch fires are rare they often cause extensive damage if not total destruction when they happen.

I would not advise removing the beams, because you do not know what else they are holding up, etc. Also, they are part of the buildings history. The beams may have been charred over the years and a charred surface does not readily burn (at Windsor they found many beams that had charred but not burnt for this very reason). However, I would not advise an open fire using the chimney flue at present. In my view there is a risk and I am certain the insurers of the building would not insure you if they knew (and non-disclosure invalidates the insurance anyway). Merely by being told about the problem and posting on this site, you now have to disclose to your insurers if you use the chimney for a fire.

A possible solution would be to line the chimney flue with an insulated liner that is brought down to a point above the Inglenook. A steel (or suitable metal) hood can be created (imagine an inverted funnel) and connected to the base of the liner. If designed and installed correctly it should not be visible from the room. This arrangement might affect the draw of the fire and it may then be necessary to install a fan to create a fan-assisted flue - the sweep may be able to advise further on this. However, this is a solution that should get you around the problems you mention.

Period Property UK would like to thank Stephen Boniface, Tony Redman and other partners at the The Whitworth Co-Partnership with Boniface Associates for responding to this question.