please tell me this is'nt true

[basic]

Doing a new installation (first fixings), was told by gaffer to drill 25mm hole through truss (3 joists bolted together) they are the main supports for the roof.

Have just been informned that this illegal due to the holes making the entire roof dangerous.

Anyone got any experience, on this subject, and what should I do?

thanks in advance

 

[Nige F]

Yeah, all my gaffers have been penis tete (That`s French) and **** is an anagram of snipe ( a bird)

 

[HandyJon]

Not quite illegal, but its against all building reguilations and breaks all guarantees etc over the trusses. Trusses should not be touched, not even to have a nail put in them except if told it's ok by an architect or structural engineer. The whole point about trusses is that they are designed to use the minimum of material (and therefore cheap) to provide a maximum of strength. Trusses should also be handled carefully.

If you are working on a development you should be going to the site manager and informing him what you have been asked to do. Problem is what happens when the site manager tells off your gaffer and he finds out it was you - that's your decision and we can't help you with that since only you know the situation.

 

[securespark]

Yeah, all my gaffers have been **** tete (That`s French) and **** is an anagram of snipe ( a bird)

If you mean d***heads, why beat around the bush?

 

[basic]

was the one who spotted it today, my gaffer who has nearnly 40 years experience said he'd never heard of it before (makes you wonder does'nt it).

The chippy says the roof may have to be rebuilt in the area effected i.e. most of it! as in left in present condition the roof could come down in the next 12 months.

p.s. did I mention that the house being built is costing 1.500,000, 6 bed house, equestrian centre, stables, garages, swimming pool, all the roofs in all areas the trusses have been drilled!!!!

I may find my self looking for work me-thinks

 

[plugwash]

well against building regs would be illegal though iirc someone has to actually get hurt before really severe penalties come into play.

building regs however are generally pretty vauge they have to be to allow for all the different situations out there.

the real question is if the fixing holes have unaccepablly weakened the part or not and without the help of a structural engineer this may be difficult to work out exactly.

why did you make theese holes? were they on the plan? were they put in because of some extra that wasn't on the plan? were they put in because of insufficiant detail in the plan?

 

[BenStiller]

Basic, it might be worth posting this on the building forum, see if they know any more

 

[ban-all-sheds]

was the one who spotted it today, my gaffer who has nearnly 40 years experience said he'd never heard of it before (makes you wonder does'nt it).

The situation is probably that he was trained when roofs were not made out of the minimum amount of balsawood and bostik - they had sodding great baulks of timber that could be drilled, nailed and hacked about with a great deal of impunity.

They may have cost more, but at least you could use the loft space - nowadays it might as well not be there.

I hate trusses, and I despise the penny-pinching attitude of the people who invented the idea. If I was having a £1.5M house built, my architect would have strict instructions not to use them, on pain of having one inserted where the sun don't shine...

 

[mapj1]

Well now some loading calculations will need to be performed by a mechanical and structural engineer approved of by the building control office to decide if the removed material is significant or not, and if it is, then bracing timbers of the same or greater strength will need laying alongside the weakened sections, and attaching in an adequate manner (usually means joist wood if straight or marine ply of bannana sghapes are needed, sandwiching the damaged sections and some very long bolts, but assume nothing at the moment.)
Then the holes (assuming these are for cables?) will need to be found a new route for.
Depending on the design of the trusses, and the method of mounting, that repair work may be easy or damn nigh impossible.
It might be faster to contact the truss prefabricators - they usually have the normal stress analysis already done, for just this sort of question.

http://www.tra.org.uk/pdf_files/pds4.pdf This data is typical of makers data they and others publish 'how to install your trussed rafter roof' type information. They also have list of truss makers accessible from the home page..