Ask our Agony Uncles ...

SUBJECT: Ponding in lead Gulley
FROM: Keith Taylor (Edinburgh)
We have recently had the felt covering of valley gutters on the roof of our New Town building stripped off and replaced by authentic lead sheeting. Unfortunately the "fall" is incorrect and after every shower of rain a ponds form on the lead, which can take days to clear. I have heard that the thermal expansion and contraction taking place in the lead at the site of the pond will eventually cause the lead there to crack substantially earlier than elsewhere. Is this true, and if so is there a cure which does not involve re-leading the roof?

Keith Taylor

The ponding itself is not necessarily a problem. However, if there is greater thermal change to this part of the lead it could result in more rapid failure. Nonetheless, if a good weight (Code) of lead has been used the likelihood of a problem is reduced. It is not only the fall that could be a problem, but the length of the sheets (bays) for the weight of the lead. The longer the bays the heavier the lead should be (the higher the Code number - usually Code 4 for flashings, Code 6 for valleys and Code 8 for larger areas - this is a very rough guide!). With many historic buildings it is difficult to lay a new lead valley in accordance with good practice because there simply is not enough room to get the falls and bays. For the time being if the valley is not leaking I would not panic. Get a technical representative from the Lead Sheet Association to visit and advise. It may be that some improvements are possible, it might need re-doing (if very poor), or you might be advised to leave well alone if the likely effective life is reasonable in any event.

Period Property UK would like to thank Stephen Boniface Associates for answering this question. Stephen Boniface can be contacted on 01279 421 500

SUBJECT: Joining properties visually together
FROM: Mark Jakes (March, Cambridgeshire)
I live in two joined properties one was an old butchers shop approx. 120 years old the other is a small cottage slightly older. After many owners and alterations the front of the 2 properties look a mess. I thought rendering the front of the property would not only finally "join" the 2 properties together but also cover all the different types of bricks used. One of the problems is that the shop front is made of glazed bricks and no-one seems to want to touch it. What do you think? should I go for rendering or is there an alternative baring in mind that the property has also been painted.

Mark Jakes

You do not say if the properties are listed or in a conservation area. If so any solution would need to be put to the Council for formal listed building (and/or conservation area) consent. How are other properties in the vicinity finished? Are any rendered or is there another form of finish (e.g. weatherboard) that is prevalent? As these were once shops it would perhaps be a shame to lose all record of such past use. Is it possible to render the ordinary brick but leave the glazed ones as a decorative feature in the elevation? Without having seen the property I cannot say that I have a solution in mind. If it is decided/agreed that the glazed bricks are to be covered in some way then I doubt if you could simply render over them. I suspect you will have to apply battens and stainless steel lath to the face of the building and render this. In fact any finish to such brickwork will probably have to be mounted on a frame away from the wall face, simply because it could be difficult to get anything other than a mechanical fixing to stay in place on the glazed surfaces.

Period Property UK would like to thank Stephen Boniface Associates for answering this question. Stephen Boniface can be contacted on 01279 421 500

SUBJECT: Dry Rot leads to concerns over replacement timbers
FROM: Richard Van Ree (Aylsham, Norwich, Norfolk)
I am renovating a listed property that has been empty for a long time. There has been an outbreak of dry rot which is being dealt with, but the local conservation officer has suggested that replacement rafters in the area of the outbreak be replaced in green oak as the originals would have been. I am concerned that with the high water content and the time taken to dry out that this is not sensible even if they are sprayed. I have been led to understand that timber water content should be below 20% in such cases and pre-treated pine would be better. Do you agree and have you any suggestions how I should handle this?

Richard Van Ree

I do not agree that pre-treated pine would be better. Oak is far more durable and if this is a listed building built with oak rafters then oak should be used for the repair. The question is therefore whether to use green oak or kiln dried? You do not comment on the source of moisture that led to the dry rot. If this has been dealt with and the area in question is well ventilated, the risk of dry rot breaking out again is remote. Dry rot is merely a fungal growth and like all such growths (e.g. mushrooms) it requires a very particular environment in which to flourish. If the environment is not appropriate it does not grow/spread. This is of course a simplified comment on the matter, but the most important aspect here is dealing with the original problem. Once that has been tackled I do not believe that green oak would necessarily lead to a renewed outbreak, unless there is a persistent high level of moisture with no ventilation, etc. If the problem of moisture has not been dealt with then whatever you use the rot is likely to return. Nonetheless, depending upon circumstances, I would generally specify kiln dried oak for rafters, as this reduces warping and other problems associated with green oak. However, it really depends on the precise circumstances. Finally, I should add that if the 'treatment' has involved the use of chemicals that are water-based, this would have reintroduced moisture into the area! Whatever you do, let it all dry out first.

Period Property UK would like to thank Stephen Boniface Associates for answering this question. Stephen Boniface can be contacted on 01279 421 500

SUBJECT: Quality of thatching material
FROM: Nick Jay (Cambridge)
I would be pleased to receive your thoughts or any information you may know of regarding the quality of thatching materials (water reed/long straw/wheat reed). I am specifically trying to compare the home grown materials in comparison of quality, longevity and appearance to their imported counterparts.

Nick Jay

You raise a matter that is much disputed in the world of thatching and I suspect your question arises from differing opinions given by thatchers. Your question cannot be answered simply in the time/space I have here, but I will have a go. Quality depends on a number of issues and the performance of the thatch on the roof depends not only on the material used but also the macro and micro climate around the property, the orientation of the property, whether roof slopes are lined, whether it is a single coat or multi coat thatch, the steepness of the roof slopes, as well as the skill of the thatcher. However, if you are simply trying to decide whether to specify (I assume you are a surveyor/architect working for Bidwells) home-grown or imported material you should consider the following. There are many good local growers of wheat and reed. It is not appropriate to simply say (as some thatchers do) that the home-grown material is not up to standard. There are many thatchers across the country using local material very successfully. There is far greater opportunity for quality control because the thatcher can go and see it whilst growing. It is completely false to suggest that growers here necessarily use more nitrates, etc. than foreign growers, the foreign material can be just as prone to the use of various chemicals and pollution as anything grown in England. There is far less quality control over imported material (how many thatchers go to Poland/Turkey to see the material growing!). If the material is not fumigated before entering the country there is a risk of foreign bugs (and I am dealing with such a case at present). In short I believe that a few importers of thatch material have inappropriately bad-mouthed local grown material because of their obvious vested interests. Thatch is a natural material and there can of course be good and bad crops. There are some poor growers. However, the traceability of a problem batch is far easier if it is local than if imported. Another perhaps more relevant issue is the question of supply. There is of course a limited supply grown locally, thus increasing the pressure to import material to meet demand. I have to say that there is of course some very good imported material, but equally there is some rubbish being brought in. If you were a Turkish/Polish grower with a bad crop, what better way to get rid of it than to ship it over to England from where it would be very difficult to trace back. I suggest that for further information you speak to the National Council for Master Thatchers Associations in the first instance. In East Anglia I would strongly suggest you speak with the East Anglia Master Thatchers Association.

Period Property UK would like to thank Stephen Boniface Associates for answering this question. Stephen Boniface can be contacted on 01279 421 500

SUBJECT: Does my 1780 Grade II Listed property need tanking
FROM: Nick Phillips (West Sussex)
I am in the process of buying a Grade II listed building (1780 Flint and timber) and have had a survey done. There are signs of damp in the living room (which I must say also has an old rotten window frame) it has been suggested that tanking the whole ground floor is advisable. I would firstly like to know if this is a good idea to try and combat any rising damp in a house this old (if this is the case). It currently has exposed beams in the ground floor walls, would these have to be removed if the rooms were tanked ?? From my understanding the tanking would just hold the dampness in the walls and may cause more damage than good....is this a fair assumption ?

Nick Phillips

Your understanding is correct. The property would not have been built deliberately to have a damp problem! Something has happened that has led to dampness. Find out what and you are a long way to solving the problem. Is the ground level too high? Have modern inappropriate materials been used in the past (plasters, pointing, etc.)? Has a modern concrete floor been laid in place of a breathable floor, that could now result in ground moisture trying to find another way out? Is it simply water ingress through the window frame? Are there gutter leaks? etc., etc., etc. Ask yourself these questions and look carefully at the property. Could some simple building works cure the problem? It sounds to me that your surveyor may not have properly understood the nature of the building and/or the problem. Too many surveyors look for the simple opt out when it comes to advising on damp problems in the scope of a pre-purchase survey - pass the buck onto the 'specialist' and advise tanking and/or chemical treatment. I suggest you get someone who really understands this type of structure to look at the problem and devise a suitable solution or tell you what repairs are really necessary.

Period Property UK would like to thank Stephen Boniface Associates for answering this question. Stephen Boniface can be contacted on 01279 421 500

SUBJECT: Do I need a survey from a specialist
FROM: Jane Bleaken (Bristol)
I am buying a ground floor Victorian flat in Weston Super Mare near Bristol and am nearly at the stage of arranging a survey. I know the property has damp problems and doesn't have cavity walls. The present owners have already had a damp course injected into the problem wall and have had it replastered with modern materials. Needless to say the damp is still a problem and the plaster is starting to come away where the wall is still very damp. My question is, would it be beneficial to have the minimum valuation survey done by the mortgage company and pay separately for a more in-depth survey to be carried out by a surveyor of my choice who is a specialist in older properties? I am concerned that the mortgage company will impose conditions and force the present owner to carry out works which may be unsuitable for this property and ultimately cost me more money.

Jane Bleaken

The simple answer is yes. Do not use the mortgage valuer for anything other than the basic valuation. Get your own surveyor/architect who properly understands the nature of the building and can advise you on precisely what to do. It is likely that the problem was mis-diagnosed in the first instance. Some of the past work (i.e. the plaster/render) may have to be removed before the problem can be resolved. It is true that the mortgage company may impose conditions. If they impose a retention it would be more difficult as you would then have to demonstrate that the work you intend to undertake is more appropriate and effective than the work the valuer suggests (usually the recommendation would simply be to comply with a 'specialist' report). Only after you have had the work carried out will they release the retained money. If the lender merely imposes a condition this is easier. You simply confirm that you will get the work carried out (you can even get a couple of 'specialist' reports to keep them happy). However, once in the property you get proper advice and undertake the appropriate work. If the lender ever seeks confirmation that you have undertaken the work (they rarely do), you can say that you have, but in accordance with the advice of an expert on such building types.

Period Property UK would like to thank Stephen Boniface Associates for answering this question. Stephen Boniface can be contacted on 01279 421 500

SUBJECT: Source of Conservation accredited surveyors
FROM: Ann Rigby-Nash (Eastbourne, East Sussex)
Have you a list of surveyors in our area who have the necessary expertise at looking at listed buildings? My husband was quite happy to purchase a property that we feel is right for us until he discovered it was listed he has doubts about taking on the task of restoration and feels that asking permission for every little change quite daunting. The words 'Grade 'II' are for him a stumbling block. I think he is worried that we will not be allowed to replace the kitchen or improve the central heating and updating bathrooms. Were would you begin?

Ann Rigby-Nash

The RICS has a Building Conservation Forum (of which I am Chair). The administrator is Kieron Higgs. He can be contacted on 020 7222 7000 (RICS main switchboard). Kieron will be able to provide guidance on suitable surveyors in your area. On the wider concerns of your husband, this is not unusual (and it is nearly always the husband who has the greater concern!), but arises from a misunderstanding. All listed building, regardless of grade, are covered by the same legislation. This simply states that consent is required for any work that affects the character of the building. The interior, exterior, curtilage, etc. are all included in this. How this is interpreted will partly depend on the attitude of the local Council, but will also depend on the listing. A more flexible attitude will generally be taken with Grade II than with Grade I buildings. Works that do not affect character (usually like-for-like repairs), or are regarded as 'deminimis', will not require consent. Certain 'reversible' works will often be allowed without consent being required. For example, the fitting out of a kitchen, bathroom, general redecoration, etc. may not require consent. The fitting of central heating is usually acceptable if properly thought through to avoid unnecessary damage to original building fabric. However, this depends on the circumstances and each property must be considered on its merits. Listing is not intended to preserve historic buildings in aspic. Listing does not prevent change and alteration, but it does require such change/alteration to be carefully considered and properly justified in terms of the building itself. Sometimes, inappropriate works, change, alterations, etc. will be refused. From another viewpoint, I often find that misunderstanding arises regarding the use of materials. Many of us involved with historic buildings recommend the use of traditional materials, which you will have noted from this web site. Such advice stems from the technical realisation that historic building usually perform better when traditional materials are used, whereas problems can arise when inappropriate modern materials are introduced. My advice to clients is that the starting point must be to properly understand the building, its history and construction. Only then can change and alteration be put in an appropriate context. The next thing is to decide on the various works, changes, etc. that you might wish to consider over time. Invite the Conservation Officer to the property to discuss these. The officer would normally be very willing to advise on which of the works will not require consent, which will but should be acceptable and which (if any) will be contentious or will be resisted. The English Heritage web site and that of the Institute of Historic Building Conservation will provide more guidance and should help assure your husband that many of the horror stories you read in the papers are the extremes and rare.

Period Property UK would like to thank Stephen Boniface Associates for answering this question. Stephen Boniface can be contacted on 01279 421 500

SUBJECT: Scottish 'A' listed property - what does it mean
FROM: Josh Gifford (Polmont, Central Scotland)
Where can I find out about restrictions imposed by the various grades of listed buildings. I have just purchased the property listed below, it is "A" listed. The building has been almost totally reconstructed internally by a third party. What procedures must I follow to make possible further internal alterations.

Josh Gifford

Category A listed building is the Scottish equivalent of a Grade I or II* listed building in England & Wales. The classification determines that it is a building of outstanding national architectural or historical interest. The legal protection relates to the date of listing, not the original building, and any material alteration that affects the building inside or out requires Planning Permission. Historic Scotland should be consulted. The curtilage and setting of such buildings is also protected. If you propose further internal alterations to a Category A listed building, you should seek professional help from an interior designer or architect with experience of working with historic buildings - the extra cost could be saved by getting the right advice. May I suggest you refer to Period Property's list.

Period Property UK would like to thank Peter Hood for answering this question.

SUBJECT: What colour can we paint our property
FROM: Mike Horton (Cheltenham, Gloucestershire)
We have recently purchased a grade II town house. It is set on one of the main roads that has served Cheltenham for some 200 years. Under the flaking paint it appears to be ingrained soot dirt etc. We are trying to decide whether to take it back to the (I think) Cotswold Stone, or to clean and repaint in a suitable colour. A decorator suggested that the overall value of the house would be more in natural stone, but (not a priority), but all of the surrounding properties are painted?

Mike Horton

Any alteration that would have an affect on the material appearance of a listed building requires Planning Permission but your Borough or District Council's Planning Department should have a Conservation Officer who could advise you and might be able to grant permission under Delegated Powers. Painting is more conservative; if the paint is flaking you should be able to scrape off any modern coatings to reveal the earlier tinted Lime Wash that could be reinstated. You can obtain this locally to you from The Traditional Lime Company at Church Farm, Leckhampton, Cheltenham, Glos. Tel: 01242 525444.

Period Property UK would like to thank Peter Hood for answering this question.

SUBJECT: How strong should the mortar be for re-pointing brickwork
FROM: John Bleackley (Surrey)
What mortar should we use ? Our property was built in 1878. A recent survey pointed out that repointing would be necessary. Unfortunately sometime in the past all the exterior brickwork has been painted. We have been advised that the paint is several coats deep and sand-blasting and chemicals may cause damage to the bricks. We have not been able to find a contractor that will work with lime-mortar and so we have opted for a 4:1 sand cement mixture - will this be suitable? What type of paint should we used to recover the walls?

John Bleackley

If your house was built in 1878 it is likely that the original mortar was bound with an early form of cement, but the basic material is sand and lime and any repointing should never be in anything as dense and strong as a 4:1 sand cement mixture. I would advise your builder to make a carefully measured 5:2 mixture of washed 'screeding sand' : lime; mix this in a tub really well using a power-drill driven plaster mixer, usually obtainable from your local Builders' Merchant or Ironmonger. Leave the mixture to soak for at least 24 hours. Just before use, mix in a half part volume of Portland cement. The old mortar should have been raked out to a depth equal to twice the width of the joint. Prior to application, both bricks and joints should be thoroughly soaked with clean water to reduce suction. There are special tools to use that make the job neater than if your builder uses a trowel. You don't suggest what sort of paint is on the bricks but they were often colour washed to even up their appearance. In recent years, modern 'masonry paint' has been applied, either as an emulsion or an acrylic resin bound coating. The latter should never be sand-blasted as this will take off the surface of the bricks as well - if the paint won't scrape off, you have to use a solvent paint stripper. Colour Wash is obtainable from specialist manufacturers given in Period Property's lists.

Period Property UK would like to thank Peter Hood for answering this question.

SUBJECT: Pine stripping
FROM: Joanne Houghton (Cheshire)
I bought a late 1800's terraced property last year. I was lucky to find many original features remained, including the original internal doors. Many coats of paint had been applied over the years, and I sent them to be stripped. Most of them are free of paint, but one of the doors still has evidence of paint in all grooves. the pine wood is very soft, and whenever I try and remove the paint, parts of the wood come away with it. Can you suggest a product/tool that would make the job easier? I'm reluctant to have the door professionally stripped again in fear of damaging it further. Can you help?

Joanne Houghton

This is a common problem. Since Victorian times it has often been fashionable to strip all sorts of earlier joinery, originally intended to be painted, back to the pine wood base. If a house is listed, one could affect the material appearance and require Planning Permission. It sounds as though the wood is very soft and the firm who stripped it were reluctant to go too far, finding the problem you have. If you asked them to remove the paint and they haven't, I suggest you contact them again, discuss your concerns and ask them to complete the job. Most paint solvents are strong alkalines that can cause permanent damage to eyes and skin - protective clothing and eyewear are essential if you have to do it yourself. It makes sense to leave it to experienced professionals - I advise you to refer to Period Property's list.

Period Property UK would like to thank Peter Hood for answering this question.