Roof replaced with heavier tiles - strengthening roof

jimbread

Hello all,

First post for me so hope all necessary etiquette has been followed. I’ve searched the existing threads but don’t seem to be able to find the answer I need...

The below was included in a HomeBuyers Report for a property we are purchasing (a 1900 Victorian terrace). It is mainly the strengthening of the roof structure due to the heavier tiles which would seem to be the main cost, sealing the gaps at the party wall would be a DIY job I should imagine. Would anyone be able to give an approximate ballpark cost please?

“The main roof is made up with timber rafters and purlins. The main roof is lined with felt. The main roof space is insulated above and between the ceiling joists.
The right hand party wall is incomplete. The gaps should be sealed to the underside of the roof covering.
The main roof covering has been replaced with heavier tiles. The roof structure has not been strengthened and improvements are now needed. Recovering the roof would have required Building Regulation approval and your Legal Adviser should confirm that local authority approval was sought and granted.
Improvements are needed to the ventilation within the roof space to prevent condensation problems from developing.
There are some horizontal splits in the roof timbers. These can occur naturally in timbers and are not considered serious.
The roof structure is not designed to accommodate large amounts of stored items, at the very most storage should be restricted to light household items.”

Many thanks all.

Mistral001

jimbread wrote: »

Hello all,

First post for me so hope all necessary etiquette has been followed. I’ve searched the existing threads but don’t seem to be able to find the answer I need...

The below was included in a HomeBuyers Report for a property we are purchasing (a 1900 Victorian terrace). It is mainly the strengthening of the roof structure due to the heavier tiles which would seem to be the main cost, sealing the gaps at the party wall would be a DIY job I should imagine. Would anyone be able to give an approximate ballpark cost please?

“The main roof is made up with timber rafters and purlins. The main roof is lined with felt. The main roof space is insulated above and between the ceiling joists.
The right hand party wall is incomplete. The gaps should be sealed to the underside of the roof covering.
The main roof covering has been replaced with heavier tiles. The roof structure has not been strengthened and improvements are now needed. Recovering the roof would have required Building Regulation approval and your Legal Adviser should confirm that local authority approval was sought and granted.
Improvements are needed to the ventilation within the roof space to prevent condensation problems from developing.
There are some horizontal splits in the roof timbers. These can occur naturally in timbers and are not considered serious.
The roof structure is not designed to accommodate large amounts of stored items, at the very most storage should be restricted to light household items.”

Many thanks all.

Strengthening, if required, could involve just additional rafters, but could also involve some major structural work. It depends on the magnitude of the increase of load and the type of roof. You will to get someone such as a chartered structural engineer to advise you how the roof is going to be strengthened to the standards required by building control if indeed it does needs to be strengthened.

Heedtheadvice

....and I would add that the structutal investigation, to determin if there is a problem should also include the supporting foundations and walls. They might not be a problem but you need confidence that is not the case. Modern property design should take into account static and dynamic loading (weight of building, snow, wind etc.) from base, through foundations, structural walls, floors, contents and roof. Not how the victorians did it -generally built massive enough but not to specific structural standards.


I would want to play it safe and get a structural opinion, now you have been pointed to areas that need checks, prior to purchase. Otherwise it would be own risk!

jimbread

Thanks - the change in load was from slate to concrete tiles... would this mean major additional work?

jimbread

So I’m that case an I right in thinking that the consensus be that a visit from a chartered structural engineer would be best before getting quotes for the work & to make sure that they consider the implications for transferring the load to the walls as well as the roof just supporting itself?

daveyjp

You need the Building Regs certificate. If there isn't one it needs one.

A house opposite me had this done many years ago. Slate to clay tiles with no roof strengthening. I can see the roof is now starting to sag at the ridges. Its an end of terrace too, so the wall may also be being displaced.

jimbread

Thanks daveyjp, our conveyancing solicitor is going to check this. Would anyone be able to give an estimate of the costs for the work to be undertaken on a worst case scenario?