Leak through wood beam

[leyasg]

Hi all,

The first issue, no doubt of many to come, in our newly purchased house G2 listed 16th century built house. There appears to be a leak coming through the wood beam on the first floor. It's not a trickle but I can feel the water. And obviously you can see the staining on the wall and water marks on the carpet.

Unsure how it was missed off the survey. It was however raining cats and dogs yesterday so it may be a one off (he says knowing he is kidding himself).

It doesn't seem to be coming from the celling, and the space above is fine. There seems to be a bell of some sort that's been installed, which we will get removed, and a lamp plug which we will need to get replaced anyway.

Thoughts appreciated before I get someone to look at it and they suggest/ do something which we regret later.

 

[Cubist]

What's on the other side of that wall? Also, is the top edge of that horizontal beam wet or does the water start juts below its bottom edge?

For now you need to go and get yourself a tub of a product called Plumbers Mait from the hardware store, together with a putty knife and some nitrile disposable gloves.

If that view of the wall is on a first or higher floor you will also need a ladder.

 

[leyasg]

What's on the other side of that wall? Also, is the top edge of that horizontal beam wet or does the water start juts below its bottom edge?

For now you need to go and get yourself a tub of a product called Plumbers Mait from the hardware store, together with a putty knife and some nitrile disposable gloves.

If that view of the wall is on a first or higher floor you will also need a ladder.

Thanks cubist. It's the first floor and an outside wall, so nothing on the other side. The bit that's wet is the middle of the wood, and below it, which is rather more worrying.

 

[Cubist]

If the internal origin of the water is from that crack/crevice - its proper name is a shake - in the beam the source of the water can be difficult to trace but it is outdoors - do not try to plug the leak internally, the water escape will just track to another internal location.

How is the exterior of the house finished? Is it exposed timbers and infill panels or has some clot rendered it?

Sadly you will need to get on that ladder to examine the external face of that timber, its interface to the infill panel, the joints to surrounding timbers and any external cracks and crevices - a 'shake' can penetrate to the full depth of a timber.

Short term you can use the Plumbers Mait to pack any obvious entry points for the rainwater to prevent further ingress. This stuff never sets and can be removed later. The challenge is finding the source and you may need to apply the putty along the full width and length of any shake or crevice between the timber and the infill panels and also the joints between this and neighbouring elements of the frame.

Hopefully, this will produce a 'short term' emergency fix. Next spring/summer though you need to plan for a large and lengthy job outdoors.

Forgot to mention, lift those carpets and examine the floor there to see if this is a recent or old problem. The floorboards and any timbers below will need to be thoroughly dried out and it will be worthwhile checking the ceiling in the room below.

 

[leyasg]

If the internal origin of the water is from that crack/crevice - its proper name is a shake - in the beam the source of the water can be difficult to trace but it is outdoors - do not try to plug the leak internally, the water escape will just track to another internal location.

How is the exterior of the house finished? Is it exposed timbers and infill panels or has some clot rendered it?

Sadly you will need to get on that ladder to examine the external face of that timber, its interface to the infill panel, the joints to surrounding timbers and any external cracks and crevices - a 'shake' can penetrate to the full depth of a timber.

Short term you can use the Plumbers Mait to pack any obvious entry points for the rainwater to prevent further ingress. This stuff never sets and can be removed later. The challenge is finding the source and you may need to apply the putty along the full width and length of any shake or crevice between the timber and the infill panels and also the joints between this and neighbouring elements of the frame.

Hopefully, this will produce a 'short term' emergency fix. Next spring/summer though you need to plan for a large and lengthy job outdoors.

Forgot to mention, lift those carpets and examine the floor there to see if this is a recent or old problem. The floorboards and any timbers below will need to be thoroughly dried out and it will be worthwhile checking the ceiling in the room below.

Thanks for the insight. There is no render. The house on that side is exposed timbers with brick, so we should be able to view. There is a wall full of Wisteria, but it's not on this side. Will also lift carpets and look through the floor.

 

[Cubist]

Good luck and come back if you're still having problems.

 

[Cubist]

If you don't know now you will soon learn that timber frame buildings move much more than other types of structure. Such movement is due to the cycles of expansion and contraction of the wood and this can frequently result in a 'shearing' effect between the mortar of bed brick infill panels than the perimeter timbers. Such continued movement of the years also causes the mortar bondings between the bricks to crumble and the panel can begin to lose its structural integrity.

You should put a close examination of all the panels on your ToDo and New Year Promise list.

 

[leyasg]

Good luck and come back if you're still having problems.

Appreciate it.

I do have one more question which I would appreciate advice/feedback on. We wanted to get bits of the house painted. But after the previous owners moved out, we've noticed there are random damp patches throughout the building house. I'm guessing during the sale they painted/hid them so it wasn't visible, and it was summer/Sept/Oct when we went so couldn't see anything other than one area. They are necessarily rising damp, as the bottom of the wall is fine (some are on first floor, with ground floor being fine). I also need to check whether the house has lime render or something more modern (and check the patches - they could be repaired poorly previously).

Would we be better off getting the whole house re-plastered, or just get the patches repaired before plastering?

 

[leyasg]

If you don't know now you will soon learn that timber frame buildings move much more than other types of structure. Such movement is due to the cycles of expansion and contraction of the wood and this can frequently result in a 'shearing' effect between the mortar of bed brick infill panels than the perimeter timbers. Such continued movement of the years also causes the mortar bondings between the bricks to crumble and the panel can begin to lose its structural integrity.

You should put a close examination of all the panels on your ToDo and New Year Promise list.

Hm, I thought lime render lasts a lot longer, so should mean decoration less often. This sounds like the opposite. This is just in the construction so I presume there isn't much else you can do about it?

 

[Cubist]

Would we be better off getting the whole house re-plastered, or just get the patches repaired before plastering?

The problem is not the plaster. If you are seeing patches of damp appearing on the interior walls it's most likely due to rainwater penetration and probably from around the timbers and their interface with the masonry. Rising damp from the ground typically does not reach a height above a foot or so from the ground level. Check the cill plates to see if you have damp patches in the plaster above them. Penetrating damp patches of interior plaster are usually fan or semi-circle in shape and its arc describes the direction of flow - the base of the fan indicates the point source of water ingress. Sorting out the ingress problems will be needed before you tackle the interior paint.

Sorry, I misunderstood. The infill panels are rendered outdoors? If so, the problem remains in terms of shearing at the perimeter but the render would prevent much of the disruption of the brick structure beneath it.

Cement mortars and renders are far more rigid and less forgiving than lime. As such they are more prone to shearing at the joints with timber. Sadly, theres no escaping the exigencies of Differential Movement with timber frames.

 

[Cubist]

Just to give you an idea of the challenge you may be facing. In the early days here I finally found the source of a damp patch that appeared near the foot of an internal. Rainwater had penetrated below the bottom edge of a first floor infill panel, tracked across the top of the beam to a main post where it then descended 10 feet before re-appearing indoors.

For when the weather improves next year you will need some oakum, caulking cotton, a mallet, an old bolster chisel, an upholsterers tack lifter and a few other minor bits and pieces. Lots of patience and a head for heights needed too of course.

Oh, and burnt sand mastic. You will need that plus the oakum to seal any external shakes that penetrate the timbers.

 

[Kearn]

Fairly standard unfortunately when the weather was like yesterday. You’re looking at the wrong side, what’s the outer like?

Frames have gaps when modern finishes are introduced. looks like modern rigid gypsum finish internally, I assume similar sand and cement render on the outside. Therefore as the timber swells and shrinks seasonally, gaps appear between frame and immovable infill.

When the wind is whipping rain sideways or its very constant, it will find its way in.

My guess, there’s an entry point at the top of the panel, somewhere under the tie beam. However, it may not be in the same location, water can track and move significantly confusing distances from entry point to exit!

There’s discolouring all along the tie, showing various leaks previously. Can you access the tie beam on the outside?

A survey would not have necessity picked this specific issue up, although any half decent surveyor would see the staining. But I’m assuming the surveyor was probably not well versed in timber frames, as there really aren’t many out there, and any that was would have given you a lot of advice already to be able to have a good idea of what’s going on here.

The fix is infill panels that can flex a bit with the frame, ideally. But if staves, wattles and daub infill with lime finish isn’t on the cards, then removing the cement render externally and then gypsum inside, then repointing what may well be a brick panel in lime, especially the perimeter with a nice hairy mix, and then replastering in lime, ideally inside and out , will go a long way. Lime is hydroscopic, so acts a bit like a sponge by holding onto water and then slowly letting it go again through evaporation, instead of letting it pour in