Restoring 17th century floorboards

[bettyb]

Hi all,
Recent home owner of a 17th ce
ntury grade 3 listed cottage.
Lifted the carpet and plywood over lay in the first floor bedroom this weekend to reveal original floorboards.
The floorboards are significantly undulated/dipping, mainly in the middle where floorboards from either side meet. Large gaps between each floorboards and repairs can be seen.
Need some advice on:
1. Whether it's possible to level the floor, mainly in the middle, and fill the gaps between floorboards somehow?
2. Best way to clean the floorboards.

Obviously getting a joiner around to have a look, but if anyone has any advice/experience in restoring original floorboards would be much appreciated. Photos attached

 

[a twig]

If you look up @Toby Newell ’s profile he has a website - https://www.newellwoodworks.co.uk/ there is a DIY guide section with extensive articles on this sort of thing

 

[bettyb]

If you look up @Toby Newell ’s profile he has a website - https://www.newellwoodworks.co.uk/ there is a DIY guide section with extensive articles on this sort of thing

Cheers matey, much appreciated!

 

[Toby Newell]

First of all, lucky you.

Seems I have been summoned! I must update my website! I have multiple 300 to 600 year old wide board oak, elm and pine floors not on there that I have restored.

Unfortunately my 'sanding floors by hand' section was never finished! Maybe I do one here at some point. Although seeing photos of £15,000 worth of equipment and the materials list might make you feel faint.

1. Whether it's possible to level the floor, mainly in the middle,

No.

You can lift the entire floor and fit firrings, very difficult with these old boards.

Sometimes you can raise the joists at the ends if they have fallen in the seat beam or wall socket but unless the floor has to come up and the celing below needs to be dropped, not advised. Either method is very expensive.

All I do is shim individual boards as I am refixing them if they all come up. FYI simply lifting a floor like this is a time consuming and specialist task!

I would learn to love the level of er, unlevel.

and fill the gaps between floorboards somehow?

There is no standard method, all my solutions are proprietary.

You can save / replace and augment the amount of fillets (sections of infill) you use, I scribe bits in, angled and even odd shaped but this takes time.

For the smallest gaps I use Lecol 7500 resin filler with sawdust (luckily I carry 350 and 550 year old oak dust on the van) For larger gaps I use two part polyester resin which I self colour myself. For the largest gaps I use two part concrete repair epoxy, self coloured again. This is a recent idea I had, seems to work well.

You would probably need 10 to 20kg to fill your floor. That's £300 to £600 if you use an off the shelf filler, but around half that the way I do it. Unfortunately you need to sand afterwards.

2. Best way to clean the floorboards

A good vacuum then scrub and wash with multiple washes of hot water, one of which should contain some washing soda. This is rarely possible on anything other than ground floors with no basement.

I sand them clean.

I have over £12,000 worth of hand held sanders and extractors. At the very minimum you would need to buy an extractor and a very good sander, at least one and a bunch of hand tools and scrapers.

And don't worry about sanding too much! Your boards are probably oak or elm and so hard to sand it will make you laugh out loud. I have a selection of the worlds best sanders and abrasives. Just as an example, using the average DIY abrasive disc, on c.17th oak, it might stop cutting after 20 or 30 seconds, that's the level we are at.

It goes without saying 99.9999% of sanding companies don't have a clue and it's 100% impossible to sand with a walk around sander (which I have also) without destroying both the floor and possibly the sander.

Obviously getting a joiner around to have a look

I would say the probability of a joiner knowing what to do and how to do it would be roughly zero. I would highly advise doing this work yourself, if you have time. These boards are £600 to £1,000 a square metre to replace (excluding 25% wastage and 25% repair, so add 50% to that) with ones that have no connection to your house.

If you break it down step by step it's actually very easy in terms of skill level, well, the fixing and filling, anyone can do it. The only two issues are knowledge and experience and the amount of time and effort, both of which are considerable. The sanding and any colouring is a bit of an art, but again the actual finishing can be learnt fairly easily if you use traditional shellac and wax.

I pretty much developed all my techniques myself over the decades by experiment.

You fix, you fill, you sand, you finish.

FYI you don't actually need to finish your floor to conserve it. Fixing it firmly is the main issue to prevent cracks propagating. You have incredibly friable edges, so these will continue to deteriorate unless you stabilise them by filling (I also use wood hardener) The only issue is you need to sand after filling, so you have to decide which you prefer, an unsanded floor or crispy edges.

 

[Toby Newell]

If you look up @Toby Newell ’s profile he has a website - https://www.newellwoodworks.co.uk/ there is a DIY guide section with extensive articles on this sort of thing

I feel a bit bad. I haven't finished my 'sanding by hand' section, so the rest would be of limited use.

 

[Toby Newell]

500 to 850 yr old timber floor - full conservation and restoration in real time

The madness begins. Set up your mobile workshop. Clean the area. Mark the jigsaw pieces. Start to remove fixings.

www.periodproperty.co.uk

Here is a soupçon of the madness. 1407 property but upper level at the back probably later 1550 addition. Mainly pine this one, possibly one of oldest in the country, dark bits are oak, with a couple of elm infills.

I managed to save the floor, including remedying cowboy building work and someone cutting the bresummer in half at the near end. We only lost four or five hand sized pieces that literally crumbled to dust. Very expensive, very time consuming and very taxing to do, but now the most solid part of the building. And how many other people in the world have a 500 year old pine floor that has been preserved for another 500 years? Not many.

My favourite board had knots over a foot long. Do you know how big a branch that is on a pine tree? Could of been 500 years old or more.

 

[bettyb]

First of all, lucky you.

Seems I have been summoned! I must update my website! I have multiple 300 to 600 year old wide board oak, elm and pine floors not on there that I have restored.

Unfortunately my 'sanding floors by hand' section was never finished! Maybe I do one here at some point. Although seeing photos of £15,000 worth of equipment and the materials list might make you feel faint.



No.

You can lift the entire floor and fit firrings, very difficult with these old boards.

Sometimes you can raise the joists at the ends if they have fallen in the seat beam or wall socket but unless the floor has to come up and the celing below needs to be dropped, not advised. Either method is very expensive.

All I do is shim individual boards as I am refixing them if they all come up. FYI simply lifting a floor like this is a time consuming and specialist task!

I would learn to love the level of er, unlevel.



There is no standard method, all my solutions are proprietary.

You can save / replace and augment the amount of fillets (sections of infill) you use, I scribe bits in, angled and even odd shaped but this takes time.

For the smallest gaps I use Lecol 7500 resin filler with sawdust (luckily I carry 350 and 550 year old oak dust on the van) For larger gaps I use two part polyester resin which I self colour myself. For the largest gaps I use two part concrete repair epoxy, self coloured again. This is a recent idea I had, seems to work well.

You would probably need 10 to 20kg to fill your floor. That's £300 to £600 if you use an off the shelf filler, but around half that the way I do it. Unfortunately you need to sand afterwards.



A good vacuum then scrub and wash with multiple washes of hot water, one of which should contain some washing soda. This is rarely possible on anything other than ground floors with no basement.

I sand them clean.

I have over £12,000 worth of hand held sanders and extractors. At the very minimum you would need to buy an extractor and a very good sander, at least one and a bunch of hand tools and scrapers.

And don't worry about sanding too much! Your boards are probably oak or elm and so hard to sand it will make you laugh out loud. I have a selection of the worlds best sanders and abrasives. Just as an example, using the average DIY abrasive disc, on c.17th oak, it might stop cutting after 20 or 30 seconds, that's the level we are at.

It goes without saying 99.9999% of sanding companies don't have a clue and it's 100% impossible to sand with a walk around sander (which I have also) without destroying both the floor and possibly the sander.



I would say the probability of a joiner knowing what to do and how to do it would be roughly zero. I would highly advise doing this work yourself, if you have time. These boards are £600 to £1,000 a square metre to replace (excluding 25% wastage and 25% repair, so add 50% to that) with ones that have no connection to your house.

If you break it down step by step it's actually very easy in terms of skill level, well, the fixing and filling, anyone can do it. The only two issues are knowledge and experience and the amount of time and effort, both of which are considerable. The sanding and any colouring is a bit of an art, but again the actual finishing can be learnt fairly easily if you use traditional shellac and wax.

I pretty much developed all my techniques myself over the decades by experiment.

You fix, you fill, you sand, you finish.

FYI you don't actually need to finish your floor to conserve it. Fixing it firmly is the main issue to prevent cracks propagating. You have incredibly friable edges, so these will continue to deteriorate unless you stabilise them by filling (I also use wood hardener) The only issue is you need to sand after filling, so you have to decide which you prefer, an unsanded floor or crispy edges.

Hi Tony,
May I thank you for your detailed response to my post. It is very informative and I will take all of this into account.
Kind regards

 

[Toby Newell]

Hi Tony,
May I thank you for your detailed response to my post. It is very informative and I will take all of this into account.
Kind regards

It's Toby, but you are welcome, see the link. Your email went to spam but all the info is above. You should be able to save pretty much all the timber and probably zero need to treat it with worm killer. The room is wonderfully wonky because your house is wonderfully wonky, the room in the link had a 305mm run out corner to corner! It's a feature, not a bug, if the construction and materials were more rigid all these lovely buildings would of cracked in two and fallen down by now.

You can micro level, ie you can get all the boards level with each other, then sand to make them flow into each other so that you don't trip / you can move furniture / move a chair easily but you cannot really level the entire floor. I mean, you could, after lifting the entire floor (and ceiling below if the lath is directly attached) fitting ply and levelling that, then refitting the entire floor.

Dipped floors are the worst. It's easier if the floors fall in one direction only. Trying to level a compound curved floor is like playing 4D chess! I do not advise it, I can show you photos of a 1680 house where I levelled the kitchen floor their handyman builder had 'levelled' it (partially as it happened, in one direction, but still a great help) I had to level each board individually and the worst areas near the bay window and entrance door took me almost day each to sort out.

I have another live enquiry in my inbox asking me to level their floor, I haven't got round to scaring them off yet.

 

[Toby Newell]

I use wood hardener on the friable areas to harden them before applying resin filler so that they break up less when sanded, the good hardener is pretty horrible stuff, it's not banned, but smells like it should be! And off gasses for a few days. It's a lot of work but the results look magnificent.

 

[bettyb]

It's Toby, but you are welcome, see the link. Your email went to spam but all the info is above. You should be able to save pretty much all the timber and probably zero need to treat it with worm killer. The room is wonderfully wonky because your house is wonderfully wonky, the room in the link had a 305mm run out corner to corner! It's a feature, not a bug, if the construction and materials were more rigid all these lovely buildings would of cracked in two and fallen down by now.

You can micro level, ie you can get all the boards level with each other, then sand to make them flow into each other so that you don't trip / you can move furniture / move a chair easily but you cannot really level the entire floor. I mean, you could, after lifting the entire floor (and ceiling below if the lath is directly attached) fitting ply and levelling that, then refitting the entire floor.

Dipped floors are the worst. It's easier if the floors fall in one direction only. Trying to level a compound curved floor is like playing 4D chess! I do not advise it, I can show you photos of a 1680 house where I levelled the kitchen floor their handyman builder had 'levelled' it (partially as it happened, in one direction, but still a great help) I had to level each board individually and the worst areas near the bay window and entrance door took me almost day each to sort out.

I have another live enquiry in my inbox asking me to level their floor, I haven't got round to scaring them off yet.

Sorry Toby*
Wow I have looked at the link, very impressive!

 

[Toby Newell]

Pictures are worth a thousand words as they say, this is my operating table. To the above I would add a couple of vaughan superbars, no idea why I left them out.

Just buy all the Japanese cats paws, I bought more during this job.

 

[Flyfisher]

I have many rooms with similar looking floors, including three attic floors in which the the boards were in much worse condition due to years/decades of a leaking roof.

Toby has eloquently described the painstaking process of returning such boards and floors back to their former glory. It's a time-consuming job and therefore expensive and because it's expensive you'll want to good final result, which means finsding someone with the skill and, probably more important, the experience of such things, which also makes it expensive. Of course, expense is not the same as the value and only the owner can really decide the value of such work.

In the case of my house, previous owners clearly decided that laying a new floor on top of the existing boards was their preferred solution. So we have rooms with new-ish (I'm guessing 50+ years) oak floors and also pine floors laid over the existing boards, which makes me think they were the choices of different previous owners. In my tenure, I decided that laying thin plywood and then carpet was approprate in the few remaining areas; the ply smooths out the worst of the gaps without 'sanitising' the overall undulations of the floor. Dead flat floors are so over-rated Only in the attic rooms was it necessary to lay a thicker plywood floor, mainly for safety reasons as most of the original boards were unsafe to walk on. Indeed the ceilings below had already suffered damage in places for that very reason.

The good thing about over-boarding is that it retains the original boards, though it does affect the door thresholds slightly. In practice, I've not found this to be a problem because almost all our rooms seem to be on slightly different levels anyway, but it might be an issue in other houses. Again, these sorts of choices will depend on individual preferences and budgets.

What would really be a crying shame (not to mention potentially criminal) would be to actually replace the original floorboards!

PS: bettyb states that the cottage in question is 'grade 3 listed'. I'm assuming this is a typing error as I've never heard of such a thing, although I know they like to do things their own way in Yorkshire, so who knows?

 

[Toby Newell]

Sorry Toby*
Wow I have looked at the link, very impressive!

The floor would take 3 to 4 weeks for me and eat up a chunk of your budget. I would say finding another contractor would be incredibly risky there is an appreciable risk they would ruin it.

If you have time then it's certainly something you can do yourself, yes it's tedious, yes there are hundreds of little steps, but the steps themselves aren't that difficult. The issue isn't that others don't have the skill, it's that they lack dedication. To be fair they are sane and I am the idiot, no one does this type of stuff to this standard just for the money, a good kitchen painter probably takes more home than I do. Part of my payment is the feeling of satisfaction which for me is very high.

That's why doing it youself is so great, you save a bunch of money, you produce something spectacular and every time you look at it you get a triple glow, one from the wood, one from the realisation you own it and the one in your head that says 'I did that'.

I'm perfectly happy to tell you what to do and how to do it.

And when you ask me questions like 'Am I doing it correctly or am I going mad?' I can offer support with answers like 'Yes'.

 

[Toby Newell]

I have many rooms with similar looking floors, including three attic floors in which the the boards were in much worse condition due to years/decades of a leaking roof.

Toby has eloquently described the painstaking process of returning such boards and floors back to their former glory. It's a time-consuming job and therefore expensive and because it's expensive you'll want to good final result, which means finsding someone with the skill and, probably more important, the experience of such things, which also makes it expensive. Of course, expense is not the same as the value and only the owner can really decide the value of such work.

In the case of my house, previous owners clearly decided that laying a new floor on top of the existing boards was their preferred solution. So we have rooms with new-ish (I'm guessing 50+ years) oak floors and also pine floors laid over the existing boards, which makes me think they were the choices of different previous owners. In my tenure, I decided that laying thin plywood and then carpet was approprate in the few remaining areas; the ply smooths out the worst of the gaps without 'sanitising' the overall undulations of the floor. Dead flat floors are so over-rated Only in the attic rooms was it necessary to lay a thicker plywood floor, mainly for safety reasons as most of the original boards were unsafe to walk on. Indeed the ceilings below had already suffered damage in places for that very reason.

The good thing about over-boarding is that it retains the original boards, though it does affect the door thresholds slightly. In practice, I've not found this to be a problem because almost all our rooms seem to be on slightly different levels anyway, but it might be an issue in other houses. Again, these sorts of choices will depend on individual preferences and budgets.

What would really be a crying shame (not to mention potentially criminal) would be to actually replace the original floorboards!

PS: bettyb states that the cottage in question is 'grade 3 listed'. I'm assuming this is a typing error as I've never heard of such a thing, although I know they like to do things their own way in Yorkshire, so who knows?

Mmmm. Covering up is the cheapest option but not the best for the floors, quite the opposite, first of all you make loads of random holes in it maybe in friable areas, breaking it, then if you don't fix the original floor itself it will continue to move, crack and break up. Yes, any plywood will reduce this differential movement a bit but the original floor will still slowly be cracking itself apart. Some areas will still be loose on the joist / beam and you introduce new differential movement of the plywood over the OE boards. So not really much of a protection! but I guess those are the rules. I guess the rule makers don't have much of a clue about a lot of stuff. The two enemies of old floors are excessive and inappropriately applied penetrative fixings and movement, internal and differential so wopping ply on top and puncturing it with random holes isn't really a long term conservation technique.

So, yars. Plonk some plywood down, lift plywood 100 years later and much of it will of turned to dust. Not realllly an advisable conservation technique! (fingers crossed noone at Historic England actually lurks in these forums ) But then how many tens of thousands of hours have the combined policy makers at HE, EH, RICS and SPAB et al spent studying, experimenting and conserving old floors? I would confidentally predict zero. I probably have two to three. Ho to the hum.

Overboarding protects from direct wear from foot traffic, which isn't really so much of an issue as it's normally so hard, many of my floors have been uncovered for centuries and still ok. The only positive might be protecting things like friable edges from direct wear from furniture, especially regularly moved items like chairs.

It's a shame to remove any existing period materials if they are in serviceable condition. One could scavenge the timber and use it elsewhere in the property. Throwing it a way would be a bit of a shame, not inso much that it would be like setting fire to or bunging £10,000 into a skip, but rather that world wide, these types of timber floors are relatively rare, even if we are blessed in this country to have a disproportionately large percentage of them.

 

[Toby Newell]

Looking at the higher res photos a bit more carefully (sorry) from the email I don't think overboarding is really an option at all here. The floor is quite badly damaged and the gaps are very large. I would advise lifting, fitting ply underneath then relaying or scavenge the good boards for a smaller area elsewhere in the property. Unfortunately it's quite poor, still likely to be lovely looking wood. Unless you are grade 1 or the interior is listed as being of special interest then you are allowed to remove and replace if uneconomical to repair or not fit for purpose.

 

[eezageeza]

I

I use wood hardener on the friable areas to harden them before applying resin filler so that they break up less when sanded, the good hardener is pretty horrible stuff, it's not banned, but smells like it should be! And off gasses for a few days. It's a lot of work but the results look magnificent.

Interesting....what is the 'good' hardener, and where do you get it ? (I assume its not the Ronseal stuff you get in most retailers?)

 

[Toby Newell]

I

Interesting....what is the 'good' hardener, and where do you get it ? (I assume its not the Ronseal stuff you get in most retailers?)

I use Rustins or Bonda. Bonda is owned by Rustins and the hardener is indentical. The Ronseal stuff is very expensive, you can use a lot. It's not magic, just a very high VOC moisture curing solvent lacquer. It only hardens where it can penetrate. If you apply it on the surface and sand it off again, it's gone. It only works on rotted or worm eaten timber where it can flow into the cracks and solidify them. It helps to stabilise friable areas before you sand them. You still might want to fill the timber afterwards. For smaller gaps you can apply a neat coat then apply a coat mixed with sawdust afterwards, or another filler.

 

[Toby Newell]

I use Rustins or Bonda. Bonda is owned by Rustins and the hardener is indentical. The Ronseal stuff is very expensive, you can use a lot. It's not magic, just a very high VOC moisture curing solvent lacquer. It only hardens where it can penetrate. If you apply it on the surface and sand it off again, it's gone. It only works on rotted or worm eaten timber where it can flow into the cracks and solidify them. It helps to stabilise friable areas before you sand them. You still might want to fill the timber afterwards. For smaller gaps you can apply a neat coat then apply a coat mixed with sawdust afterwards, or another filler.

If you have punky wood, ie parts of timber that have been partially rotted, sometimes this happens with no change in dimension, just maybe a change in colour or a bleached area, then this might soak in on really porous parts. On normal wood it just sits on the surface. It's not magic. It's most effective on friable parts with lots of worm galleries (my use case) or rotted parts that have partially desicated.

It's of limited use. Technically it's not a wood hardener, only heat, pressure and time do that, it's a wood consolidator.

It's usually best to cut out rotted areas and let in new bits, but if for any reason you can't this might help.

I am not totally convinced how great it is as I fill woodworm with resin and sawdust anyway, but it seems to help stabilise weak parts during sanding. It's quite expensive, has a very unpleasant and powerful VOC odour and is pretty useless on vertical surfaces.

I use it on very old and very valuable floors which have extreme woodworm damage where you want to try and save every last inch. It's another tool but cutting out, replacing and filling are more important.

One of it's main strengths is being moisture cured, especially if you are treating exterior timber that may be slightly damp. For dry timber a thin two part epoxy resin might work just as well, although hardly cheaper and hardly less smelly! The epoxy should dry to form a stronger matrix and is often used before using an epoxy filler.

 

[Lacan07]

View attachment 13037

View attachment 13038

View attachment 13039

That floor would look amazing if sanded and varnished, I wouldn't bother trying to straighten it, etc. Now you've revealed it what other choice do you have? Carpets are naff and putting anything else over it would just be a bodge.

 

[eezageeza]

If you have punky wood, ie parts of timber that have been partially rotted, sometimes this happens with no change in dimension, just maybe a change in colour or a bleached area, then this might soak in on really porous parts. On normal wood it just sits on the surface. It's not magic. It's most effective on friable parts with lots of worm galleries (my use case) or rotted parts that have partially desicated.

It's of limited use. Technically it's not a wood hardener, only heat, pressure and time do that, it's a wood consolidator.

It's usually best to cut out rotted areas and let in new bits, but if for any reason you can't this might help.

I am not totally convinced how great it is as I fill woodworm with resin and sawdust anyway, but it seems to help stabilise weak parts during sanding. It's quite expensive, has a very unpleasant and powerful VOC odour and is pretty useless on vertical surfaces.

I use it on very old and very valuable floors which have extreme woodworm damage where you want to try and save every last inch. It's another tool but cutting out, replacing and filling are more important.

One of it's main strengths is being moisture cured, especially if you are treating exterior timber that may be slightly damp. For dry timber a thin two part epoxy resin might work just as well, although hardly cheaper and hardly less smelly! The epoxy should dry to form a stronger matrix and is often used before using an epoxy filler.

Thanks Toby, interesting and useful! I'm currently working my way through 22 window frames (softwood, and about 20 years old, but badly maintained) and have used the Ronseal stuff with some success, but have always wondered if there was something better out there.