loft conversion pictures inc

[krazyk555]

hi i am just going 2 convert my loft in to a toy room i stay in a 1970s bungalow semi detached the trusses are W shape i have started cutting them and fitting the straight up just lookin for some advice and do i have 2 contact the local building department and is this a good way 2 open up space in your loft cheers

trusses sizes are 2 3/4 x 3/4 inch


joists are 5 x 3/4 inch and gap between joist are 440 mm View media item 2566 View media item 2568 View media item 2569 View media item 2570 View media item 2571 View media item 2572 View media item 2573 View media item 2574 [/img]

 

[Joatmojo]

Be very, very careful my friend, your roof could well collapse around you!

Truss roofs are fashioned exactly and precisely in the most efficient form, to take the most amount of strain and stress, with the least amount of material. Removing, altering ar messing about with any element of it may prove to be disastrous - although a real expert in the subject may suggest otherwise.

Great photos, very useful, and I don't wish to be alarmist, but I have noticed a pet hate of mine: I don't know about anybody else, but I've always cringed at the use of 'Hedgehog' plates (or whatever they are called!) on truss work, I can just see them working loose over time with the constant expansion and contraction of a buildings fabric; I would have to bolt on something more substantial than that, or at least add a few heavy duty screws!

 

[masona]

i have started cutting them and fitting the straight up

Can you quickly show us the photo's of what you have done, gang nailed trusses are not design to be cut or altered.

I also don't wish to be alarmist but this could be a serious problem.

 

[Shytalkz]

Jeez, be careful...

You need to put in the supporting structure that stops the trusses acting as trusses, before you go chopping out any of the diagonal members.

If you've not had any structural design done, I suggest that you get hold of an SE to sort this for you before you go any further.

Joat: have you ever tried getting one of those gangnail plates out of a piece of timber? They are tighter than a nun's chuff.

 

[Joatmojo]

They still dont fill me with confidence - mother nature can be extremely brutish at times.

But I've not much experience of them really, it's just that I am a teeny bit old fashioned, and like to see good old tried and tested methods used in traditional buildings.

 

[Shytalkz]

I know that, at first glance, they don't look to be much, but when you've inspected a trussed roof that's failed as a result of a gas explosion and found every gangnail still attached to bits of timber and the failure being the timbers themselves beyond the plates, it kinda gives one some confidence as to how they behave!

 

[noseall]

OH MY GOD!

STOP NOW!

you read about this sort of thing happening in the newspapers, or see it on the news.

 

[Shytalkz]

The gangnail plates are still attached though

The OP hasn't responded - do you think he's in a similar situation after a day spent chopping the roof about?!

 

[noseall]

he has removed or appears to have removed all lateral, diagonal and chevron 4" x 1" strapping and bracing.

i can also see the remains of a gang nail or hydro nail lying on the loft ceiling.

 

[noseall]

mind you, up there in Scotland the roofs are extensively stiffened by the solid sarking.

phew!

 

[Shytalkz]

I hadn't looked that closely at the photos, but have now - third truss in, diagonal tie from the ridge removed and a vertical put in. So now the rafter is spanning loads further than it was, the forces in the truss are no longer triangulated...

Sarking will create a diaphragm and a much stiffer roof than the battened affairs we have down this end of the island, but even so.

Mad.

 

[Symptoms]

krazy - put it all back the way it was!!! If you still want to create a toy room (?) up there get some advice from, as Shytalkz says, a structural engineer.