Rotted sill plate

[murraysnudge]

That's the construction I'm familiar with in victorian buildings Masona, but Dave has said the wall is on top of the wall plate?

 

[TexMex]

I have seen solid walls built like this (ie wall plate built into the wall). I think this was an accepted practice in the early 1900s (if not common). There was a school of thought that it gave greater lateral support for the walls, (as the joists tied the floor into the walls). I believe by the mid 1940s it was being advised against, and considered a bad practice.

 

[DaveJ123]

Well, as I said, there's brickwork on top of the plate. So it can't really be a sleeper wall.

I'll let you all know what happens and what it is, for reference purposes. Builder said he'd phone tonight, so don't know when he'll actually come.

When he does, maybe I should get him to post y'all an explanation.

 

[masona]

If you can, rip all the wallplate out and replace with engineer bricks or concrete lintel. I can't see the point of having brickwork resting on timber which is the weakest point. Having said this I've not seen it yet or picture

 

[DaveJ123]

Ok, just had an FMB builder visit. The first one didn't phone back btw - why are they so unreliable?

Anyway, I asked about the wall, and he screwed his face up and said, "no, this wouldn't be a cavity wall in a property like this; it'll be solid". He said the 'black bricks' are breeze blocks, which would have been put there because the builders weren't able to drive nails for skirting boards etc. into brick. The sill plate, he said, was totally rotten and not supporting anything. He recommended replacing all the joists in the room (mentioned woodworm), as well as the whole plate in that room as it'd likely all be rotten. I agree about the plate, not so sure about all the joists. Woodworm holes don't mean we've got woodworm now, after all. He said no chance of the wall falling down because the bricks are acting like a lintel - and it would have fallen down already if it was going to in view of the state of the plate.

He seemed decent, and if he is, it'd be damn useful to know a good builder. He said he could do it within a week or two ('easy, one day job') - which is good. But it's bad because he can't be very busy, presumably? Or, maybe even busy builders can still fit in a day of work (?) I'm tempted to do it myself, but not sure about cementing the plates and dpc in position. If he does it, I think I'll insist on him removing the plate in sections and replacing as he goes.

So, notwithstanding masona's aversion to wooden sill plates under masonry , and based on this sparse information, does anything he said sound unreasonable to anyone?

 

[murraysnudge]

Dave, you described the property as pre-1940's but I didn't think breeze blocks were used until the 50's. The bit about the builders not being able to drive nails into bricks to fit the skirting sound like nonsense to me. Before masonry nails, it was common practice to build in wooden wedges between the brick joints to nail into for skirting and door frames.
I agree with you that woodworm exit holes are just that, and don't mean there is any activity now. Even if there is, if the timber is not weakened by woodworm it can be treated.
I have already said what I would do as I have already done similar work, i.e. replace the wall plate with brick and build-in steel joist hangers.

 

[DaveJ123]

murraysnudge,

This site does reckon that breeze blocks were used back then, and the things do look like 'em to me, fwiw.

http://www.homeownersales.co.uk/1930.html

But your not impressed with matey's theory about their applications. Hmm.. b*gg*r! Hope he's not a BS merchant.

Fwiw, this site reckons cavity walls will be at least 30 cm thick (mine are more like 24 cm), so more evidence you guys were right.

http://www.saveenergy.co.uk/howto/insulation/walls.cfm

I take your point about hangers, but some of the brickwork right there doesn't look too good. If I were to do the job, it'd be safer to toe nail a joist on top of a sill plate than me trying to drill holes in and repair brickwork to hold it, methinks.

 

[masona]

He said no chance of the wall falling down because the bricks are acting like a lintel - and it would have fallen down already if it was going to in view of the state of the plate.

If the wood is rotted then how come it acting as a lintel

 

[murraysnudge]

Ok, I'm surprised that breeze blocks existed before the 50's but I am the first to say I don't know everything. I have never seen a 9" solid wall built with a mix of block and brick though. Perhaps it is a regional building technique local to your area? (masona or Tex, have you ever seen this?)
We're assuming that this is as the house was built and hasn't had any work done in this area.
The width of a cavity wall is usually about 250mm plus the plaster depth, which ends up about 265mm. A solid 9" wall will usually be 220 plus the plaster depth so your 240 sounds about right for a solid wall.
I've just thought that you could look at the gable end in the loft to see what the brick bonding looks like.
If the brick wall had been free standing with no return at the end or any buttressing walls then it would not be stable with the wall plate rotted but it will get support from the rest of the house walls.
I think we would all still like to see a pic though. You must know someone with a digital camera?
The builder may be competent but I'm not impressed with him wanting to replace all the joists just because of a few woodworm holes.

 

[DaveJ123]

Masona, read the quote again mate - the *brick* is acting as a lintel.

Murraysnudge, yep, I was going to see what I could see in the loft. But hoped it was settled. Maybe I should anyway.

One problem is that all you can see of the brickwork above the plate is an area about 2 feet wide (including 2 joists) and the height of the joists. Above that, there's a glimpse of a bit of red brick and the black stuff here and there. To photograph the black stuff in context you'd need a boroscope to make sense of it. This is while hanging upside down with my head through the bottom of the sink unit. Below that, is the edge of the wooden plate that appears fixed with mortar above and below on top of two visible layers of brickwork foundation (orientated with all ends out of the wall - i.e. running parallel with joists) and Regarding the joists.

The first two joists i.e. those that are visible, are wet rotted. The one running parallel next to the wall is so bad near the corner I could probably tear it in half with my hand. The next one is rotted at the end near the plate and also as it crosses the first sleeper wall. That sleeper's plate is rotted too. I would be surprised if several of the joists aren't affected where they touch the main wall sill plate. I've a feeling this is combination of long term dripping from the sink and water getting to the plate from elsewhere.

There is a large pile of the sawdust like material (wood worm poo?) on the foundation floor a few joists along next to the wall. Don't know if that's evidence of recent activity(?)

 

[TexMex]

My father was a brick layer in the 40s and 50s. (sadly departed in 1974). He told me of the Breze blocks in the wall method for skirting board attachment. My mothers house also has them (although she has a cavity wall construction, but lives on an estate where my father was a bricklayer!).

If this is a solid wall (which I would bet my life savings on), the cross bonding of the brickwork will give some support to the inner "skin" of the wall, in a corbelling type of manner.

I would not consider, however, putting the wood back in the wall. As a belt and braces type of approach, I would probably.

1) Buid a Seperate sleeper wall next to the existing perimeter wall. Ensuring that the wall plate on this is tight against the existing joists.
(and don't forget the DPC beneath it).

2) Working on a section at at time. Remove the old wall plate and cut the end off the joist and fill with bricks (ensuring tight joints).

3) Move on to next section and repeat.

Usint this method, the floor will be supported througout the job, and, even be adding support to the brickwork.

Having said this. I would still recomend that you get an experienced brick layer in to carry this work out.

I wouldn't be surprised if the pile of sawdust has been sitting there since the house was built! Someone may have cut the joists, or whatever, on that very spot.

I can't say much about woodworm, (not my field), but nothing that your builder has said, seems to sound particularly wrong. "Bricks acting as a lintol", could just be his way of describing corbelling, in lay mans terms.

One day job, sounds about right, unless joists need replacing.

 

[masona]

Masona, read the quote again mate - the *brick* is acting as a lintel.

At the moment it is but how long for ? The extra weight will push onto the top of the floorjoists as it not supported where it's rotted. Now where that picture ? All I know is, you're somewhere in the south east without a digital camera

 

[DaveJ123]

Thanks for that info about the breeze blocks, Tex, imparted by your sadly departed father. And the suggested procedure too.

Regarding this solution you all seem to agree upon (new sleeper wall to support ends of joists + bricking in the plate gap), it sounds like the best solution to me now, too (maybe you should re-check your calculations ). But I suspect my mother's going to say "you've been listening to those people on the internet again....let the builder fix it the way it was" - or words to that effect.

Btw, I've received the builder's estimate "to replace any rotten floor joists/boards and wall plate.." in area of 3.9m2 : £570 inc VAT. Seems a bit stiff...

 

[murraysnudge]

I don't disagree with the new sleeper wall solution Dave, and it's how the house should have been built. I personally would use the joist hanger solution as I would find it less work, but like a lot of building methods there is often more than one way to do a job.
I can't comment on the estimate of £570 but have you seen the price of beer, perhaps that's the going rate for a day's work in the affluent South.
Remember that an estimate is not the same as a quote. If the builder gives you an estimate, and not a quote, the final bill can be higher because of additional unforeseen work. Always agree to a quote for the whole job.
We'd still like to seea pic though?

 

[DaveJ123]

Yep, thanks. I knew 'estimate' wasn't 'quote', but didn't know whether to press it. The way he described it, he was assuming that most of it would need replacing. I thought it might turn out less - which, as you imply, might be a dangerous assumption. But if he's decent, I might be tying myself to a larger figure. I'll mention it anyway. I've also asked for a couple of references from previous clients, and a start and finish date, so I'll see if comes up with it; he seemed a bit reluctant about "bothering previous clients" and mentioned a building control officer instead. But that's what you need to get into the FMB, so he could just have a tame one of those. He did seem decent though.

I'll see what I can do about a picture- not promising anything - and there really is nothing much to see; just the edge of the plate and two rows of brick on top.

cheers