Upgrading/Replacing joists in loft....?

[The Riviera Kid]

Hi folks,

I have a long list of things to learn about in readiness for future upgrades/modifications (as the regulars will know).

The joists in the loft (ceiling joists I presume) appear to be about 2"x4". Am I right in thinking they'd need to be double this to support a floor for a future loft conversion?

Would this usually be a straight swap, or is it possible to somehow strengthen the ceiling joists in any way?

Thanks in advance.

 

[freddiemercurystwin]

There is usually an awful lot more involved in a loft conversion involving steel beams and structural engineers calculations. You'll need to post some photos and/or a description of the existing roof and the existing spans and which if any walls are loadbearing. As your house is fairly modern you have probably got trussed rafters which are a pain to convert. Essentially you need a few steel beams to support the rafters before you cut away the trusses. Have a look at this tasty thread: //www.diynot.com/forums/viewtopic.php?t=137740&postdays=0&postorder=asc&start=0 Your steels probably won't be as beefy but this is what you will need to do.

A rule of thumb for steel beam/timber joist sizing is that the depth of the beam/joist is 1/20th of the span.

 

[The Riviera Kid]

Hi freddy, you are the zen master of quick replies lol.

Yeah, I appreciate there's loads more involved. We have a W beam configuration up there, which will be a pain to convert. Thanks for the comprehensive reply and pointer to that post.

It's one of the jobs that I'll likely be leaving to a professionals. I do however like to understand how it all works for my own piece of mind.

Thanks.

 

[freddiemercurystwin]

Hi freddy, you are the zen master of quick replies lol.

Or just bored!