Wall plate sourcing?

[Adam W.]

I think that the existing timbers look like softwood - arguably oak would be overkill (although it won't need treating and looks beautiful). Interesting that the rafters look as if they're pairs of 4 X 2. You haven't told us what the existing timbers are - it does have some bearing (pun intended!).

The crucial dimension for this wall plate (which also serves as two lintels by the looks of it) is the vertical height - resistance to vertical deflection under the weight of the roof - esp. in the centre of the doorway - is the key issue. Any horizontal width >= 100mm would be fine, subject to it being properly anchored to the walls.

If you do go for a larger overall section, you can always split it - on the vertical axis - into two pieces bolted/nailed together to make handling/lifting easier (and possibly reduce the timber cost into the bargain).

You're right. It's normal for the wall plate to be softwood, but generally green oak is easier to source than large scots pine sections.

That's why I suggested oak first. I may have got the dimensions mixed up, but I still recommend replacing like for like, whatever it is.

 

[KevinLycett]

Oh, I forgot.

If you make the wall plate any bigger or smaller, then you'll have to screw around with the purlin as it will change the geometry of the roof.....and you probably don't want to do that.

Thats very helpful, so that seems as I thought, exact like for like is pretty essential.

 

[Adam W.]

Pretty much.

It should be an easy replacement and you can use that acro prop you have to lift all the ends of the rafters clear at the same time, so that you can slide the new wall plate into place.

I'd recomend repairing the wall at the right too. You can use folding wedges to straighten the masonry up and pull them out once the mortar is set and repair the holes. Or just cut them off flush, which is what I do with timber frame repairs if they are not too deep.

 

[KevinLycett]

Folding wedges sounds genius. I was thinking I’d have to dismantle and rebuild where the mortar had washed out. What exactly are folding wedges? I mean do you make them, or buy them…? Also I’m assuming I need to use lime mortar?

 

[Adam W.]

I make mine out of 1" oak, as that's what I have lots of. They are just one wedge on top of another to give you a very accurate and strong jacking effect. I like them to taper 1 1/2" over 8" or so, so that they are not too steep. If the joint is wide, I just chop the thin ends off to give me a bit more thickness to start off with and gently knock them in.

You can just wedge it all up and put the timber in, then point it all up with a bit of lime mortar in the spring when the risk of frost has passed.

 

[KevinLycett]

Thanks again for your advice. I was quite daunted by this job but its starting to look do-able!

 

[Adam W.]

It's very straight forward, just take a deep breath and dive in.

Clear your site and take your time. If you need more help just ask, as it's the kind of work I've been doing for years.

I'll see if I can find the photo where I jack the roof up to repair the wall.

 

[Adam W.]

Here you go...

I just prop the ends of the beams on this one and lift the roof off so that I can get the whole wall out to repair it.

The wall had been forced out of plumb when the old truss collapsed, so I renewed the trusses and shoved the wall back into position to straighten the house up.

It's back on the ground and there's just the brickwork to do before I started on the right hand side. That took a bit more fixing and I used needles to lift the whole wall plate off the posts to get the wall out and repair it.

I've done this all the way around the building, doing a section each summer. There's one little bit to go, but I'm leaving that so that I can take it out when I put the staircase in, as the post timber is quite large.

 

[KevinLycett]

Here you go...

I just prop the ends of the beams on this one and lift the roof off so that I can get the whole wall out to repair it.

View attachment 124444View attachment 124445

The wall had been forced out of plumb when the old truss collapsed, so I renewed the trusses and shoved the wall back into position to straighten the house up.


View attachment 124446

View attachment 124447

It's back on the ground and there's just the brickwork to do before I started on the right hand side. That took a bit more fixing and I used needles to lift the whole wall plate off the posts to get the wall out and repair it.

I've done this all the way around the building, doing a section each summer. There's one little bit to go, but I'm leaving that so that I can take it out when I put the staircase in, as the post timber is quite large.

Amazing