Roof support split. Any ideas?

[bunters1976]

Hi

If anyone could assist we would appreciate it.

We are looking at buying a house. The roof looks in reasonable condition and it has got signs of a repair with a new diagonal joist.

There is however a split in one of the roof supports.

I have no idea how serious this is and if it is pretty catastrophic or not. If may even be old damage prior to the repair which is to the right of the photo. There is a support for this bean shown in the photo, but no support to the right of this suggesting to me (rightly or wrongly) this isnt holding the entire roof up???

If anyone could assist or give any advice at all we would really appreciate it.

Thanks

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• bunters1976
• 16 Mar 2014
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• bunters1976
• 16 Mar 2014
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• bunters1976
• 16 Mar 2014
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• bunters1976
• 16 Mar 2014
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• bunters1976
• 16 Mar 2014
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[catlad]

Well its certainly an issue some more pic's of the loft as whole would help and some of the roof outside.

 

[footprints]

Certainly looks recent the wood is very clean, time to make a surveyor earn his crust!

I wonder if it has had a new roof recently, concrete tiles are much heavier than the original terracotta ones.

 

[tony1851]

I'm going to stick my neck out here and say that it's not a serious structural problem.
The crack is over the support, and half-way down the depth of the purlin, which is the best place (or least worst place!) for it to be.
The bending stress in the purlin over the support will be nil - the only issue will be shear, and there will be ample cross-section of timber left to accomodate the shear force.

 

[bunters1976]

Thank you all for the responses. If it helps I have added a few photos. I cant get anymore internally straight away as I have to go through the agent.

As before there has been a repair to the end of the roof. The diagonal beam on the corner has been replaced. The location of this is in yellow.

The location of the photographed split is on the red bead on the blue dot.

Apologises if it appears a child has done the diagrams.

Is it possible that whilst repairing the yellow line bean this would have caused this damage and it is not an issue not? Would it be suitable to botl another post to it to add strength or would it need full replacement?

Thanks again for any advice.

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• bunters1976
• 16 Mar 2014
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• bunters1976
• 16 Mar 2014
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• bunters1976
• 16 Mar 2014
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[tony1851]

Would it be suitable to botl another post to it to add strength or would it need full replacement?

A third option would be to do nothing as it's not going anywhere, but get some off the price anyway. But that's only my opinion; if you sell the house in 2 or 3 years time, the same concerns will be raised by the next buyer and surveyor.

If you added another post, you would need to provide support for that post, and there might not be an obliging wall or other suitable structure below. Any attempted repair to the purlin, eg by sistering, would only draw attention to the fact that it has split.

Perhaps the more realistic long-term option would be complete replacement, but as to cost....???

PS the yellow valley beam which has been replaced - was it rotted? If so, it may have been caused by break-up of the roof tiling allowing water ingress at that vulnerable point. Has it been re-tiled recently?

 

[bunters1976]

Yeah thats true. As long as its not going anywhere then I think I can live with it.

Is it as simple as replacing the split piece or is it more complicated than that?

There is no sign of rot on the beams and everything looks dry. From the outside the roof looks solid. The tiles do not look new though so I assume it was redone a while ago.

But clearly I am no expert.

Thanks for your help!

 

[ree]

When they replaced(?) the valley rafter (the diagonal red beam), the weight from the main roof hip rafter, and the intersecting ridge of the pediment roof could have brought pressure point forces on to the purlin below.

The above is just a guess really.

But the future (temporary) stability of the purlin would depend on how many props have been used, and if all the correct cut roof parts (jacks etc.) were re-joined as they originally were.

 

[ree]

On second look, the purlin seems to be a pretty light section.

 

[tony1851]

When they replaced(?) the valley rafter (the diagonal red beam), the weight from the main roof hip rafter, and the intersecting ridge of the PEDIMENT roof could have brought pressure point forces on to the purlin below.

The above is just a guess really.

But the future (temporary) stability of the purlin would depend on how many props have been used, and if all the correct cut roof parts (jacks etc.) were re-joined as they originally were.

translate; 'pediment' roof (US) = 'gable' roof (UK)

 

[catlad]

It looks like the chimney has been removed so it could have happened then, and yes that split piece of timber looks like a rafter to me.

 

[tony1851]

I that split piece of timber looks like a rafter to me.

By jove, the gentleman could be right! well-spotted!

Hard to judge the scale but if those rafters are 4x2, or even 6x2, it would put a different complexion on matters.

 

[bunters1976]

Yes that's correct the chimney has definitely been removed and was just behind the location of the split.

Sorry for my ignorance... What impact does it have if it is a beam?

 

[TheVictorian]

Could this be reinforced by bolting a steel plate to it?

 

[bunters1976]

I don't know. The consensus appears to be that I can and the roof isn't falling down ?