Purlins not supported at party wall

[Bl55YJS]

(Removed at OP request)

 

[cdbe]

A short length of angle iron bolted to the wall underneath will adequately support it.

 

[slawit]

I would just go belt and braces and then some, get a metal angle bracket made in 10mm mild steel, the width of the Perlin 150mm long on one side (this is what the Perlin will sit on) the other leg 300mm long add a little triangle piece wielded into the corner. Have 6 * 9 holes drilled in the leg then bolt the whole thing to the wall with 8 * 80 concrete screws or similar. Wouldn’t stop me buying the house.

 

[Bl55YJS]

I would just go belt and braces and then some, get a metal angle bracket made in 10mm mild steel, the width of the Perlin 150mm long on one side (this is what the Perlin will sit on) the other leg 300mm long add a little triangle piece wielded into the corner. Have 6 * 9 holes drilled in the leg then bolt the whole thing to the wall with 8 * 80 concrete screws or similar. Wouldn’t stop me buying the house.

So essentially like a gallow bracket on the wall underneath the timber? Do you think there’s any risk that actually connecting the timber to the wall could damage the party wall as the roof structure expands and contracts through heating cooling etc?

 

[robinbanks]

If it helps, slawit is describing something like a "gallows bracket". Other kinds of L shaped bracket with a diagonal support would also work (or you could mount your gallows the "wrong way round" and drill extra holes in it - typically the angle iron ones don't have holes in both legs and one of the legs overhangs the corner") - mezzanine flooring brackets, etc

Supporting the purlin wont cause any more distress to the wall than it would having the purlin buried in it

I think I'd have something fabricated that was more like a metal plate with an L or U shape welded to it that went round the purlin end but didn't screw to the purlin so it's supported how a wall would have supported it originally, something like this thing I just happen to have lying around:

 

[slawit]

Not really but if you are concerned about that just don’t screw the Perlin to the bracket, this will allow sideways movement and expansion in the Perlin, any vertical heave will be taken up by the roof itself.

 

[martygturner]

Fixed these a few times, but never sure why it was an issue, its the way it was deigned, the shared chimney stopped penetration of the purlin so they strutted it to a collar on the ceiling.

Used C24 treated joist in 3ft lengths, notched at the purlin ( 5mm - just enough to cup the purlin) and bolted to the wall @ 150mm centres inline with the purlin direction so about 45 degrees in your case. Gets round any expansion contraction issues.

 

[johnny2007]

As advised, can all be done by a competent diyer.
Won't stop me buying the house.

 

[Bl55YJS]

Fixed these a few times, but never sure why it was an issue, its the way it was deigned, the shared chimney stopped penetration of the purlin so they strutted it to a collar on the ceiling.

Used C24 treated joist in 3ft lengths, notched at the purlin ( 5mm - just enough to cup the purlin) and bolted to the wall @ 150mm centres inline with the purlin direction so about 45 degrees in your case. Gets round any expansion contraction issues.

Thanks Marty, sounds like a logical approach. Out of interest, how would you deal with the right hand purlin where it sits very close to the chimney? I assume there wouldn’t be room for the timber below the purlin when following the load path of the purlin

 

[freddiemercurystwin]

What's the issue anyway, it's been like it for 125 years, the timbers all look as straight as when they came out of the mill and it's been re-roofed in the meantime. Ahh yes the issue is the surveyor covering his back.

 

[cdbe]

What's the issue anyway, it's been like it for 125 years, the timbers all look as straight as when they came out of the mill and it's been re-roofed in the meantime. Ahh yes the issue is the surveyor covering his back.

Completely, but the "repair" done now will have time to age and look like it's been there forever so the issue doesn't even exist when the house is sold in the future.