Wall plate... If this is the wall plate, it's not all on the wall! Problems?

[Oxbow16]

Hi again

 

Apologies for another question so soon...  Having removed the concrete render from the back of our house, I've also removed the soffits which I'll replace after repointing.  I don't know much about building, but I presume the wood on top of the wall is the wall plate?  On the right hand side, this seems to be as I would expect - firmly on top of the wall, leaving space in front for ventilation, with small pieces of wood to attach the soffits to.  But as it goes along the wall, the wall plate gets further and further away.  By the time it reaches the left hand side, it is no longer on the wall at all!  

 

Aside from potentially being wrong, the other problem is that I plan to install ventilated soffits.  In that area they won't be very effective because the timber pretty much spans the gap the soffit will span, so not much air would get passed.  

 

Bit stuck as to whether I am over worrying, it is totally wrong and needs remedial action, or something in between.  Any help would be fantastic.  

 

The first photo shows the full length.  
The second shows only half the length, looking in the opposite direction, and starting from where the wall plate/timber starts to move away from the wall top.  I've put a green line on to help show the timber edge.  
The third is a closer look at the timber off the wall.
And the fourth is the same, but looking from behind).

 

Please ignore all the plastic bags etc which have just been put in to prevent unwanted visitors.  

 

Many thanks

 

 

 

 

 

[Oxbow16]

More photos:

 

 

 

[BotusBuild]

Looking at the different colouration (is that a word?) of the underside of the wood in the photo it would appear that any one (or combination) of these has happened:

1. Has the wall been rebuilt or repaired in the past that you know of? and been rebuilt in the wrong place?
2. Has someone hit the wall and shifted it backwards? (just putting the option out there)
3. Has there been ground movement that has resulted in the wall moving as well?
4. Has the roof been repaired in the past that you know of? and the repair resulted in the wood ending up in the wrong place?

[Canski]

Is there another wall plate slightly higher up the rafter than this ? ( Just a thought)

[BotusBuild]

2 minutes ago, Canski said:

s there another wall plate slightly higher up the rafter than this ?

Good call

[markc]

Ive got to go with @BotusBuild it looks like that was once on the wall. Some pics showing more of the roof would help

[joe90]

That roof has “spread “, needs pulling back somehow, what’s the other side like?

[ProDave]

7 minutes ago, joe90 said:

That roof has “spread “, needs pulling back somehow, what’s the other side like?

Not so sure.

 

The outer edge of the soffit looks to be the same distance from the wall all along.

 

What appears to have happened is that "wall plate" has moved out.  That would imply it is not fixed to the rafters?  If that is all that is supporting the roof then it is on the verge of falling off the wall.  Usually the wall plate is on the inside of a wall. I would want to have a look and see if anything else is supporting the roof.

[joe90]

1 minute ago, ProDave said:

That would imply it is not fixed to the rafters?

Fair comment, if that’s the case much simpler to rectify .

[ProDave]

2 hours ago, Oxbow16 said:

 

 

 

 

Looking at this picture, the movement has happened a long time ago.  The soffit is relatively new and the spacers suggest when the present soffit was fitted this "wall plate" was already displaced.

 

If you can confirm the roof is adequately supported by something other than this timber, then there may be no need to correct it?

[saveasteading]

3 hours ago, joe90 said:

That roof has “spread “, needs pulling back somehow,

Ok we had this.  

In our case the roof had spread over many decades, due to natural forces but also rot reducing the strength of some timbers.

 

I would predict that you have a tied roof construction and this will always have an out-thrust at the wall, and the timbers sag and move outwrds. It just depends how much.

 

The chance of pulling it back is minimal and might cause more damage. a secondary plate that picks up the load is an option, but that may then slide too.

 

Any pictures of the roof construction?

 

[joe90]

4 minutes ago, saveasteading said:

In our case the roof had spread over many decades,

Having looked again at pic 4 I think this is correct, no ceiling joists tying the rafters and fixed to the wall plate and higher ties are less efficient, again what’s the other wall like?

[Simplysimon]

8 hours ago, ProDave said:

That would imply it is not fixed to the rafters?

don't know about that as in pic 4 it looks as though the the birds mouth on the rafters is still at the wallplate

[ProDave]

34 minutes ago, Simplysimon said:

don't know about that as in pic 4 it looks as though the the birds mouth on the rafters is still at the wallplate

What is puzzling me, is if it has spread, then originally the roof edge was not parallel to the wall?  (it is now)

[joe90]

24 minutes ago, ProDave said:

What is puzzling me, is if it has spread, then originally the roof edge was not parallel to the wall?  (it is now)

Is it, @Oxbow16 we need more info, personally I think the roof has spread one end judging by the pics but without more info ? What’s the wall plate like the other end? What’s the wall plate like on the other wall?

Edited August 31, 2022 by joe90

[Oxbow16]

Thank you all so much for all the replies and enquiries.  Very helpful and very kind.  It may be a day or two before I can get answers and additional photos together, but as soon as I have I'll be back.  

 

Thanks again in the meantime

[Oxbow16]

Hi 

 

Apologies for the delay.

 

I should have made it clear that this is not a gable end.  It was originally, but an extension was added a few decades ago.  The extension is stepped in from the old house by 30cm at the back and that’s where we're looking.  (For reference, the old part of the house and extension are flush at the front.)  It looks like this from above:  

The old part of the house has solid walls, around 550mm thick, and is random rubble I think.  (For reference, the extension is 300mm cavity walls).  The top section of the wall of the old house – where it meets the extension – has been taken down in the loft.

 

The roof construction in the old part is “A” frames with principal rafters, and purlins supporting the smaller rafters.  The tie beams / collar beams are at joist level.  The joists run perpendicular to the tie/collar beams.  There’s no principal rafter at the problem wall plate area, I guess because it would have been the gable end originally with the wall providing support.  The last purlin before the extension joins has been replaced at some point, presumably when the extension was built.  A support pillar has been built in the loft on top of the old wall for this purlin.

 

In the extension, there are no tie beams.  The joists run opposite to what they do in the old part – so from front to back of house.  Atop the joists there’s a sizeable timber running from the top of the old wall into the new gable end.  This supports the rafters.  

 

In the house, the ceilings slope where they meet the external walls.  Hence why none of this is visible in the external photos.  And why the wall plate is not visible in the loft.

 

Hopefully that makes some kind of sense and along with the photos below explains what we have construction wise, but happy to try to answer any questions or post more photos.

 

To answer some of the points raised above…

 

The different colouration of the underside of the wall plate wood… The concrete render has been hacked off the wall, which – along with removing the soffits – has revealed the wall plate issue.  The colouration change shows where the render was.  Perhaps they felt that the render was enough support for the wall plate.  

 

On 31/08/2022 at 11:46, BotusBuild said:

Looking at the different colouration (is that a word?) of the underside of the wood in the photo it would appear that any one (or combination) of these has happened:

1. Has the wall been rebuilt or repaired in the past that you know of? and been rebuilt in the wrong place?
2. Has someone hit the wall and shifted it backwards? (just putting the option out there)
3. Has there been ground movement that has resulted in the wall moving as well?
4. Has the roof been repaired in the past that you know of? and the repair resulted in the wood ending up in the wrong place?

 

1 to 3 = not that I know of.  4 = it’s an old house that has had various changes over the years (i.e the extension).  The tiles are concrete so definitely not original!  It’s the same tiles on the old part of the house as it is on the extension that adjoins it.

 

On 31/08/2022 at 11:51, Canski said:

Is there another wall plate slightly higher up the rafter than this ? ( Just a thought)

 

Not that I can see, but because that part of the roof is not accessible, I couldn’t say for sure.  I’ll have another look though from both ways.  There is a big lump of concrete beneath a rafter. which may have been an attempt at adding additional support?  See red circle here:

 

 

 

 

On 31/08/2022 at 22:21, joe90 said:

What’s the wall plate like the other end? What’s the wall plate like on the other wall?

 

I can’t access the wall plate on the other side (front of the house) to see unfortunately.  So I can’t answer what’s going on there.    

 

On 31/08/2022 at 12:44, ProDave said:

Looking at this picture, the movement has happened a long time ago.  The soffit is relatively new and the spacers suggest when the present soffit was fitted this "wall plate" was already displaced.

 

Yes, soffits and fasicas are new-ish – think they were installed around 10-15 years ago.  With the render discolouration on the underside of the wall plate as well, I think @ProDave is right to say that the timber was already like that when the new soffits etc were fitted.  

 

Finally, to add:
- looking at the offending section of wall plate in my first post, the first section of timber starting at the corner, is 56cm long.  
- From the corner to the window lintel is around 80cm.  
- At the window, the wall plate half sits on top of the lintel
- There is no rafter behind pvc barge boardy bit.
- The rafters are fixed to the wall plate as far as I can see.  

 

So based on all of the above, is there adequate support without the wall plate being on the wall?

 

Sorry for such a long post!

 

And huge thanks again for all the help.

 

 

 

 

Edited September 5, 2022 by Oxbow16

[joe90]

Wow that’s comprehensive, well done. IMO it’s not going anywhere with that new purlin, new brick support and substantial timber. I think it did “spread” like I originally said but much too late to pull it back but as it’s going nowhere I don’t think it’s a problem.

[ProDave]

+1 to the above.  I think the work done has stabilised it.

 

If as we suspect the present soffits were fitted about the time of that work, then if there had been further movement you would have seen the soffits separating from the walls.  I don't think you had seen any movement there which means the stabilising work has worked.

[Radian]

What's the glass wool insulation doing up there in between the rafters - apart from reducing the air circulation around them? The correct place for it is down on the floor with the vermiculite. Along with another 200mm or more!

[Oxbow16]

Great - that's a relief.  Very pleased that all should be well as it is   

 

When I install new ventilated soffits after the re-pointing, with the thin gaps around the over extended wall plate be enough to get air up into the loft.  If not, any ideas how I can improve the ventilation there?  

 

On 05/09/2022 at 09:54, Radian said:

What's the glass wool insulation doing up there in between the rafters - apart from reducing the air circulation around them? The correct place for it is down on the floor with the vermiculite. Along with another 200mm or more!

 

I've no idea why they decided to have insulation at joist level and at rafter level.  The glass wall in the rafters is quite thin.  It's bonded to the underside of the felt.  Not sure if it was bought like that or added.  But anyhow, sorting the insulation is on the list of works to be done.  As is making sure there is adequate ventilation by adding the ventilated soffits where there are none.  

 

Many thanks for all the help with this 

[Oxbow16]

On 06/09/2022 at 23:34, Oxbow16 said:

When I install new ventilated soffits after the re-pointing, with the thin gaps around the over extended wall plate be enough to get air up into the loft.  If not, any ideas how I can improve the ventilation there?  

 

Any ideas guys?  

 

Cheers

[joe90]

Well you have enough gap/air this end 🤣, it looks like the gap further back if stuffed with something 🤔, you only need about 10mm continuous (mostly) fir air. Is the other side ventilated (crossflow).

[Oxbow16]

Great, thanks @joe90

 

I'll have a measure up but I think the gap is likely to be 10mm+

 

The "stuffing" is just temporary until the wall is repointed. 

 

Yes, the soffits are ventilated on the other side so all good there.  Not sure why they chose to ventilate one side but not the other...

 

Cheers

[joe90]

2 hours ago, Oxbow16 said:

Not sure why they chose to ventilate one side but not the other...

 

I worked on a neighbours house and previously the mortgage company when they bought it insisted they put in soffit vents, I discovered when I stripped the roof that the brickwork was tight against the back of the felt so no ventilation at all got into the loft!!!!,, I cured that by removing the top row of bricks laid between the rafters 🤷‍♂️