Slipped Perlin

[Cod Roe]

I have a slipped perlin in my Victorian terraced house which is currently perched on a brick:

I would like to take the weight off it and rebuild the triangle of brick work that was once around it. Any suggestions as to how best to go about this work much appreciated.

Thanks

[Harry Bloomfield]

That looks like perhaps a chimney in the lower left of the picture(?).

My suggestion would be to gently take the weight of the timber against the chimney, at an angle and on both sides - using something like a pair of car scissor jacks. Options for rebuilding then would be to reinstate the brick work as original...

Or perhaps make up some shuttering around it and fill with concrete. I'm no expert, so the latter idea is open to discussion.

[Roger]

The message from Cod Roe contains these words:

This is the sort of thing where you might need to swallow your pride and get a structural engineer in to advise as there is at least a faint possibility that the roof has started to spread. But if it has moved it hasn't moved very far and to my mind it needs stabilising in its current position rather than attempting to jack it up.

There is only so much that can be gained from a photo but it seems to me that the bottom corner of the purlin was actually below the line of the brickwork to start with and that little V it sits in was original. Is the brickwork below in good condition? It looks as there there might be a repaired crack running down the righthand side and if that is the case the situation might be more serious.

You need something solid to prop from and your photo doesn't show what is below or how far down the loft floor is. The loft floor joists (ceiling joists of the room below) are almost certainly too weak to support individually but it just might be possible to spread the load with a really thick plank and support with a short Acro prop or even a heavy duty car jack.

You will need to consider whether the purlin that continues across the next space needs supporting as well. If you had a convenient hole through the wall you could kill two birds with one stone by putting something really solid through the hole (short length of RSJ perhaps) and have a prop both sides of the wall.

If it was me I would be tempted to find some strong thin bricks or stone so that the lower of the 2 purlin ends can sit firmly on a thin brick and the higher end (which currently does sit on a full size brick) on another thin brick one course up.

But be careful, be very very careful. You don't want to make the front page of the Daily Prejudice.

[Andrew Mawson]

perhaps)

brick

If Victorian, that sarking felt with hessian in is definately not original. Has the roof covering been replaced at some time with something heavier? Perhaps an original slate roof replaced by concrete tiles? In which case get the structural engineer in pdq and check that the roof structural timbers are capable of taking the load now imposed.

AWEM

[dg]

I would pull the dropped purlin back against the upper one behind it - via either a big g-cramp or fit a bolt and tighten the two together.

This will pull it up and then you can pack the bearing with slate or fit a timber wedge.

I would not bother relaying the bricks in mortar - the purlin is not going anywhere.

dg

[The Natural Philosopher]

PURLIN Or purline. Never perlin..

Looks a totally crap bit of brickwork, put in by a cowboy..

And the roof was slated up before the mortar had set..that woodwork looks too good for Victorian. And the mortar is very grey portland as well.

Bet you that roof and timberwork sagged and rotted and was replaced, and the chippies decided to 'put in a brace' but screwed up on the brickwork.

Oh. They braced it because they didn't have a purlin long enough - there are two there joined right? And the bastards have no cross ties either..relying on the joists..

Yeah..get a car bottle jack and some planks to spread the load and jack it up an inch and put in some decent brickwork with a 2:1 mortar mix.

I'd check the rafter to joist area as well.might be some rot or slipped nails.

[The Natural Philosopher]

Ah but its nice to do a workmanlike job.. I would actually drill through the purlins and use TWO coach bolts to clamp em

[mail]

Dear Cod, I agree with the excellent advice to check what the covering is and if it is not the original slate(?) call in an engineer - particularly if some idiot has put in concrete tiles without support. Assuming it is slate I would then stablise your purlin laterally by whatever sensible means available - probably raking shores in timber, and take the weight vertically with a trench Acrow prop supplemented by two suitably cut angled fillets on the bottom of the purlin - one to the front - one to the rear (of the house not the photo) to provide a flat support for the purlin. Once supported I would use a off-cut of a plank linel or a concrete block or engineering brick - any suitable material to act as a bearing that has been specified by an engineer. I assume the purlin that is overlapping is that of your next-door neighbour and the post that suggested a common approach is clearly right. In theory, I suspect you should be complying with the party wall 1996 Act(?) before you so much as touch a brick. If for any reason you want to join the purlins together (an I would definately check on the advatages or not of this with an engineer) the right product to use is a bolt and 2" plate washes NOT coach bolts which are the invention of the Devil when it comes to any sensible form of timber engineering. (The coach bolt heads pull through the timber when subjected to any significant load.) Chris

[R]

Looking at the other pics on your photo album site I reckon you'll need an engineer in to advise. Especially with that dodgy chimney and tiles around it.

They don't look Victorian to me