Changing roof trusses

[markiii]

Looking to move house and I promised myself a garage lift this time.

New place has the height in principle but the truss design is not helpful

kind of like this



there's a couple of feet to be had if the roof trusses were modified, its a double garage fraction under 6mx6m floorspace

Obviously this would require some structural calculation so would be getting the professionals in.

However I'm trying to get a feel for what kind of cost modifying this would come in at?

anyone had experience in similar?

[whatxd]

It may be better just to rip the whole lot off and put attic trusses on by the time you messed around with the associated costs of doctoring the existing trusses. There are plenty of companies that offer instant quotes. You'd need 11 of them.

[Aluminati]

As above. Attic trusses.

[LooneyTunes]

Folk are jumping towards attic trusses but these still have a bottom chord, so won t solve the problem: they give you more space inside the loft area but won t create the box you ll need for a lift to raise a car into: for that you need a raised tie or coffer truss design (that will lift the tie out of the way of the lift).

Roof truss companies are generally pretty easy to work with so I d suggest giving one a call in the new year.

Edited by LooneyTunes on Sunday 28th December 07:11

[whatxd]

LooneyTunes said:

Folk are jumping towards attic trusses but these still have a bottom chord, so won t solve the problem: they give you more space inside the loft area but won t create the box you ll need for a lift to raise a car into: for that you need a raised tie or coffer truss design (that will lift the tie out of the way of the lift).

Roof truss companies are generally pretty easy to work with so I d suggest giving one a call in the new year.

Edited by LooneyTunes on Sunday 28th December 07:11

Sorry I interpreted the op incorrectly. I assumed he wanted habitable space but if it's a higher celing so to speak then raised tie truss.

[smokey mow]

An engineered solution will likely involve a couple of steel purlins of some description, which will then allow for the ceiling ties to be raised or removed.

It can also normally be done by doubling up the original rafter with a new much larger rafter so you don’t then need to fully strip the roof off.

Your structural engineer will certainly be able to advise on the best way of doing things.

[Gtom]

It’s going to need a heavy duty ridge beam and the rafters sistering up.

You will be able to get an engineer calculate it all and also have the steel fabricated in 2 or 3 sections if needed.

Easiest way would be to get all the extra timbers in and fixed, birds mouthed ready, knock a hole in the gable end and slide the steel in.

[markiii]

thanks guys its the cost I'm trying to get a handle on, to see if its practical

[TA14]

markiii said:

thanks guys its the cost I'm trying to get a handle on, to see if its practical

I can't work out what your structure is from your posts. If you can slide in two or three pieces of steel then that will take the vertical load although you might still need a new beam or truss at the front over the door and perhaps horizontal restraint to the walls - £3K?? If you end up taking the roof off and re-roofing, £6K??

[smokey mow]

markiii said:

thanks guys its the cost I'm trying to get a handle on, to see if its practical

An engineer should be charging you between £250 - £500 for the calcs, once you have these you’ll be in a much better position to get accurate quotes for the work.