DIYnot
Local | Network
   DIYnot > Forums
Local | Network
DIYnot Network Local DIYnot Network Local  
  Forum IndexForum Index     RulesRules    HelpHelp     Join FREERegister Free     About CookiesCookies     SearchSearch     LoginLogin 

buying pre-made trusses and rafters


 
Post new topic   Reply to topic    DIYnot.com Forum Index > Roofing and Guttering
Search this topic :: View previous topic :: View next topic  
Author Message
garyo

from United Kingdom

Joined: 11 Apr 2006
Posts: 694
Location: Berkshire,
United Kingdom
Thanked: 44 times

PostPosted: Sat Dec 05, 2009 11:02 am Reply with quote

I need to make a roof for a new porch / front extension, which is 4.5M x 1.8M. The roof is a lean-to design with a hip end on one end. (compliant with building regs)

Is the 'done thing' to buy the wall plates, trusses etc pre-made from a supplier who'll build them to my dimensions? Is there much to be saved by attempting to make it all myself? I like the idea of buying it as a kit to be honest!

Cheers

Gary
Back to top
 Alert Moderators

If you do not want to see this advert, click here to login or if you are new click here to join free.
thatbloke

from United Kingdom

Joined: 27 Oct 2009
Posts: 1646
Location: Suffolk,
United Kingdom
Thanked: 8 times

PostPosted: Sat Dec 05, 2009 12:08 pm Reply with quote

it would obviously be cheaper to make it your self but why not ask a firm for a quote then price up the raw materials your self , then you will see the exact difference in cost
Back to top
 Alert Moderators
cumbrianroofer

from United Kingdom

Joined: 30 Nov 2009
Posts: 110
Location: Cumbria,
United Kingdom
Thanked: 11 times

PostPosted: Sat Dec 05, 2009 1:54 pm Reply with quote

something of that size you could form yourself 4x2 timber and a measure twice cut once rule dont think you would get trusses for a porch 4.5m wide by 1.8m spar length much cheaper to do it yourself or get a joiner in someroofes would do it to included in roof price
Back to top
 Alert Moderators
noseall

from United Kingdom

Joined: 02 Feb 2006
Posts: 19963
Location: Staffordshire,
United Kingdom
Thanked: 1194 times

PostPosted: Sat Dec 05, 2009 4:08 pm Reply with quote

I personally prefer to build my own cut roof. It is wrong however to assume that this is cheaper than buying trusses. Sometimes it is and sometimes it isn't.

A hip end will take a bit of thought and skill but otherwise, piece of cake.

The beauty about building a cut roof is you can build it instantly and to the exact dimensions that you wish to build it.

P.s. i have just took delivery of the 6"x2" timbers for the latest cut roof i am building and they are 7.4m long.... in one single length! icon_eek.gif
Back to top
 Alert Moderators
garyo

from United Kingdom

Joined: 11 Apr 2006
Posts: 694
Location: Berkshire,
United Kingdom
Thanked: 44 times

PostPosted: Sat Dec 05, 2009 7:03 pm Reply with quote

The hip joint is probably the thing that worries me the most.

Are there some fairly simple rules to follow in terms of building regs - 600mm gap between trusses, use 4x2" timber, and whatever zinc hangers you find in the local merchants?

Something I've not mentioned is that I'd like the space to be usable, for a small amount of storage, so will fit a hatch and probably lay chipboard over the insulation. Will the building inspector want to look at my truss cross section and want me to prove, somehow, that it can deal with snow/wind loads?

Thanks

Gary
Back to top
 Alert Moderators
noseall

from United Kingdom

Joined: 02 Feb 2006
Posts: 19963
Location: Staffordshire,
United Kingdom
Thanked: 1194 times

PostPosted: Sat Dec 05, 2009 8:38 pm Reply with quote

Roof truss manufacturers provide calc's for their products.

Don't be surprised to find little usable space in the roof void.
Back to top
The following user says thank you to noseall for this useful post:
garyo (7 Dec 2009)
 Alert Moderators
garyo

from United Kingdom

Joined: 11 Apr 2006
Posts: 694
Location: Berkshire,
United Kingdom
Thanked: 44 times

PostPosted: Mon Dec 07, 2009 1:04 pm Reply with quote

Thanks Nose,

So you do your calcs yourself then?

I agree re: the amount of space. I've not actually sketched out the likely cross sections involved, so I've no idea how realistic that aim is. I don't expect to be able to get a person up there, but the kind of space you can stick a head into an keep the odd box of decorations etc.

Cheers

Gary
Back to top
 Alert Moderators
noseall

from United Kingdom

Joined: 02 Feb 2006
Posts: 19963
Location: Staffordshire,
United Kingdom
Thanked: 1194 times

PostPosted: Mon Dec 07, 2009 5:14 pm Reply with quote

garyo wrote:

So you do your calcs yourself then?



A cut roof is designed and built according to span tables and is usually specced-up on the drawing, i.e. section sizes for rafters, joists, purlins, plates etc.

As i said previous, roof truss companies supply a data sheet with the truss delivery that details calculations, strap positions, spacings and node bracing positions.

Edit to add: Actually it is the structural engineer that has the final say but the architects/designers take the credit. icon_lol.gif


Last edited by noseall on Mon Dec 07, 2009 5:19 pm, edited 1 time in total
Back to top
 Alert Moderators
noseall

from United Kingdom

Joined: 02 Feb 2006
Posts: 19963
Location: Staffordshire,
United Kingdom
Thanked: 1194 times

PostPosted: Mon Dec 07, 2009 5:16 pm Reply with quote

EDITED: oops button malfunction
Back to top
 Alert Moderators
Search this topic :: View previous topic :: View next topic  
Post new topic   Reply to topic    DIYnot.com Forum Index > Roofing and Guttering All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
Similar Topics   Replies   Views   Posted 
Free estimates for someone buying a new house. 3 340 Tue Jun 08, 2010 12:14 pm
advice needed on sagging roof on house I am buying 5 3240 Sun Feb 11, 2007 4:51 am
Looking at buying a flat roof house 3 500 Mon May 18, 2009 6:48 pm
block layers made a balls of my roof 9 260 Sun Aug 21, 2011 2:24 pm
Roof tiles no longer made. 5 200 Thu Dec 15, 2011 10:30 am


 
DIYnot
Find an Expert | Find a Supplier | Search DIYnot.com
Network | Advertising | Newsletter
DIY | DIY How To | @home | DIY Wiki | DIY Forum
By using this site you agree to our Terms of Service / Disclaimer.
Please read our Privacy Policy. Copyright © 2000-2014 DIYnot Limited.