Where to get advice about old timber framed buildings? Longish

[Nick]

A happy new year to one and all.

I recently inherited my late fathers house. Late Tudor farmhouse and a big old barn of a place (no pun intended). Listed G2. Timber framed, brick infill to the ground floor, wattle/daub or similar to the 1st floor, peg tiled roof. The exterior is rendered & painted, timbers are exposed throughout. All timbers appear to be oak and in good condition mainly. Over the last few days I've had the chance to have a good look around and what I see dismays me greatly. The wiring, plumbing & ch have all been completely renewed in the last 10 years and there are no known problems with these. However, I can't find any other aspect of the old place that does not need major attention. Most of the problems I know how to deal with, but one in particular needs professional advice I feel. The main rooms on the ground floor are about 25ft square. The ceilings are supported by 12" x 12" beams in a + arrangement. The cross is central to each room and formed by a single timber span with the 2 'arms' double morticed/tenoned to that single span. Joists of 9"x6" are morticed/tenoned to the 2 arms at about 18" centres. A very substantial structure. In one room only the single span is bowed downwards by about 3" and this is immediately noticeable. Equally worrying is that the tenons of the 'arms' have pulled out by at least an inch on each side. I presume this is a result of the main timber bowing. As you might imagine this worries me greatly as a failure of these timbers could be catastrophic. To the best of my knowledge this problem has arisen quite recently, certainly within the last 20 years. I could jack up the ceiling beams and put a 12x12 oak prop beneath the centre of the cross. This would effectively destroy the appearance of a lovely room. I would be more inclined to jack the structure up beyond level and then secure the 2 arms together using a substantial metal strap or straps. I'm worried about what effects any jacking operation might have upon other parts of the structure. Thus I feel expert advice is needed. Anyone know where I can ask for such advice please?

Many thanks

Nick.

[The Natural Philosopher]

Where are you nick?

If in east anglia, have some good carpenters who can fix this stuff.

I'd say a structural engineer would be first port of call - pay for a full structural survey. A couple of hundred probably and worth every penny.

[Anna Kettle]

Thats true in other parts of the country too

Agreed (is this a first NP?!) but be sure you speak to a structural engineer who is experienced in old buildings like this. Call the SPAB free helpline to get a list of names.

Anna

~~ Anna Kettle, Suffolk, England |""""| ~ Lime plaster repairs / ^^ \ // Freehand modelling in lime: overmantels, pargeting etc |____|

01359 230642

[Nick]

morticed/tenoned

Thank you for the sound advice. I'm in Bucks, not a long way from Heathrow (unfortunately). I guess a full structural survey is a good way to start into this venture. I'd be pleased if a couple of hundred would cover it but I fear that won't be the case. Most certainly a couple of days as least.

Do you know of any good tilers ? I'm told there are about 120,000 in total and some repair is urgently required. We used to use an American Indian from Devon. Best tiler I have ever seen. He went off the scene some years ago and all since have done more damage than good.

Nick.

[Peter Crosland]

The first thing to remember is that in a listed building, particularly of that age, there is very little that can be legally done without getting formal listed building consent from your local planning authority. Indeed is a criminal offence to make many changes without such approval. Unfortunately it means your will have to wade through a lot of bureaucracy. You need to choose a structural engineer or surveyor who specialises in such buildings. It does not come cheap and the figure quoted by someone else is absurd.

Peter Crosland

[Peter Parry]

You will find you are entirely within the grasp of the local authority Listed Building Mafia. It would be foolhardy to spend anything without speaking to them first (not that it will give you any comfort - but it may save a small amount of money initially).

Yes - two excellent ones in South Herts who do a lot of work in the Sth Bucks area

(also my neighbour, but their workmanship is superb).

[The Natural Philosopher]

No it isn't, because I don't know of them Anna :-)

Indeed.

[The Natural Philosopher]

No. It took an engineer less than a couple of hours to identify the crucial weaknesses in my old cottage, and predct what I would find when the walls were dismantled.

And come up with three suggestions all of which were sound, and two of which had not occurred to me.

There are many reputable tiling firms, but don't even go there until you are sure you have a sound structure to pin them to.

Its vital that you stabilise the structure, and make good any rot, and pin any weaknesses. In the meantimne all you should do is temporarily make good anything that lets in water, but its not worth spending oodles of cash on: Because I suspect that yu will need to strip back and make good any rotten timber work, and if the structure is collapsing a bit, use steel or whatever to pull it all back together - the engineer will know the key vital areas - and maybe have to replace rotten roof timbers as well.

Once you have done that get Anna to advise on re-doing the details - any lathe an plaster walls that you have had to remove to get at vital bits etcx..

She's the antique craftsman. I am just an engineer :-)

Though not specifically of the structural sort sadly.

[The Natural Philosopher]

That was all it actually cost me,from such a firm.

Perhaps its absurd, and they were being nice.

It wasn't a detailed survey, just a 'what is happening, why, and what are my options' Tht cost me about 150 quid.

The indicated costs involved were such that not being listed, I decided to re-make most of the structure, and what I found when doing it made me go for a complete rebuild ultimately. It wasn't that great a cottage, but the location was fabulous.

you can see the result at

if you like.

In the process I invoked the same engineers again to validate the new structures. That cost 350 quid for a day or two of calculations.

Nothing compared to the final cost of doing the work.

[Aidan]

Try:

discussion forum, but more oriented towards old buildings. "An American Indian from Devon"?

[sylva]

You could consider asking the resident carpenter at the weald and downland museum. IIRC he is a qualified building surveyor and qualified in grading structural timber. He is also an old friend I have not met up with for some years.

AJH

[Roger]

If I understand this correctly the construction method has created a major weakness right at the point on the main beam where it needs to be its strongest. Old timber is often bowed but that would have been a gradual process when the structure was relatively young. A sudden movement in old age suggests to me that the main beam has failed and is now being held up by the floor above and the minor joists as much as by any remaining stiffness of its own. If that is so you need to put in Acro prop (or similar) to prevent the next stage of collapse. Don't forget to spread the load if the lower floor is suspended or in any way suspect.

If you have any heavy furniture above shift it at least to the edges of the room but not until you have propped the beam.

[Nick]

bureaucracy.

I fear you are correct in all points mentioned. Nick.

[Nick]

I have been in the clutches of the planning dept. for some years. The listed building mafia is all I need right now! I will contact them, I mean the tiling firm!

Nick

[The Natural Philosopher]

I would not be so concerned.

My rooms - brand new in green oak - show that much gappage anyway from shrinkage.

You get about 10" across a span of green oak - so a 9" beam could easily show 1/2" each side.

My 12" beams after 2 years are showing about 1/4" each side, and there is more to come yet, as its reckoned they do about 4" a year.

And 3" dip is nothing for a bit of timber of that size. May have been cut from a not particularly good bit of timber when green and it may have simply shrunk to that shape under drying out, and possibly central heating.

If the main span is not rotten, then there is little to worry about I'd say.

[Roger]

The message from The Natural Philosopher contains these words:

I agree that if the movement is ancient there shouldn't be much to worry about.

I don't have the original message to look at (on a different computer

240 miles away) but I thought the op said he thought the 3" sag was recent in which case it is a totally different ball game. Timber gets stiffer as it seasons and more brittle with age.

If it is some peculiar effect caused by recently installed central heating why was only this beam effected and why when shrinkage along the grain is so limited would the beam bow. The op could still differentiate between bowing and breaking though. If the beam looks like 2 straight lengths with a hinge in the middle then it is likely to cracked at the hinge if it is merely bowed then the chances are it hasn't broken.

If the ends of the beam are merely built in to the wall there probably will not be sufficient rigidity for the beam to behave as a 'built in' beam in the engineering sense of the term and the bow should extend from one wall to the other. If however there is sufficient mass at each end (or the beams continue through the wall to provide a jetty for the upper storey) the shape would be rather different with 2 convex sections joined by a concave section. With only 3" deflection that might be difficult to distinguish.

[Bruce Tanner]

The Society for the Protection of Ancient Buildings (SPAB) do lots of books and leaflets and also have a free advice line - suggest you ring them.

Timber moves, and you shouldn't necessarily be concerned - it's not like a modern house. It can absorb movement. In a house 100s of years old you wouldn't expect every joint to be a perfect fit.Very few of mine are!

Installation of central heating often causes movement, even in wood 100s of years old. So can the installation of other "modern" things like the installation of double or secondary glazing, or the replacement of lime-based mortars and plasters with portland cement-based materials.

You really need to find out if movement is still taking place (the usual method is to stick little glass plates over the joints, and see if they crack over time)

Compare your thick oak beams with a modern roof truss made of 2" or 3" softwood and you will see that these old houses were massively over designed in terms of loads on the beams. Your 12" beams are most unlikely to be about to split!

I've lived in an old a half-timbered house for many years, and I too was alarmed at many things when I first moved in. But after a while you realise that "imperfections" abound, and in fact that is part of the character. The roof line is so crooked it looks like it might collapse; some of the bedroom floors slope so much you feel you are rolling out of bed; and, as you say, some beam joints look like they are coming apart. But it's been standing over 100s of years over extremes of weather, and it's not about to fall down now!

[Peter Crosland]

Don't get too taken in by Peter's paranoia about the so called "listed building mafia". The important thing is to make sure you ask them before you start any work. That way if they do object you will not have to spend lots more undoing work they won't authorise. Remember that they are human and doing their job. A lot depends on how you treat them which seems a basic point many ignore. Confrontational tactics seldom get the best results.

[Michael Mcneil]

He sounds well off I'm sure he has a kidney and a few other bits he can auction of on E-Bay or somewhere to keep the heritage people happy.

Flog the thing and get a relic in Wales or a disused croft in the Outer Hebrides. If you have to make repairs at least there is only you it will all come down on. Or rather if it does, and you survive, you won't have to reinstate it to someone else's specs.

[N. Thornton]

Hopefully you are now aware that what you proposed to do in your first post is off target, and quite likely even criminal.

These are the folks that will help most:

's also SPAB.

What you do to the building, down to almost every last detail, is dictated by an official, and this includes what colour (or what shade of white) you paint the windows. I'm not kidding. If the house contains pictures these may also be covered by the listing, and selling one could put you in jail. Also the curtilage of the building will also normally be covered by the listing. It is essential you understand what youre dealing with, what listing actually means.

A 3" bend is unlikely to be any cause to do anything, though I couldnt possibly guarantee that to be the case. However any work you do will be required to be an exact restoration of the original in every respect, including use of the same type of wood and so on, so none of your earlier repair ideas are likely to be legal.

What will you do with the house? If you plan to sell, repairs of the things you mention would make no sense financially. A grade 2 listed building is a different thing to a terraced house, where a quick tart up pays. In most cases you won't see an increase in value that would pay for any work you do.

Re surveyors, I would have a good long chat on period property forum before engaging one, or in fact doing anything at all.

g'luck

NT