Joist & wall plate straps (1)

[Backlash187]

Hi all,

Once again looking for some help on my self build. Flat roof kitchen extension with additional utility room. I have wall plates installed, ready for rafters. Wall plate bolted to wall with hangers at one end, and overhanging the horizontal wall plate to create soffit & facia on other.

My drawing calls for "Flat roof joists to be strapped to wall using batt straps at 450mm ctrs, to prevent uplift", which is fine. Looking at regs these should be 1000 long (or at least easier to make them this to be safe). *See image attached*.

My query is that if I am strapping every joist, do I have to install wall straps also?

I see some call for these at a max of 2m between each. The drawing doesn't mention them, and I was initially going to install both for belts & braces, but wanted to check what the experts think!

Once again thank you for taking the time to help!

Will

 

[Backlash187]

Hi all,

Once again looking for some help on my self build. Flat roof kitchen extension with additional utility room. I have wall plates installed, ready for rafters. Wall plate bolted to wall with hangers at one end, and overhanging the horizontal wall plate to create soffit & facia on other.

My drawing calls for "Flat roof joists to be strapped to wall using batt straps at 450mm ctrs, to prevent uplift", which is fine. Looking at regs these should be 1000 long (or at least easier to make them this to be safe). *See image attached*.

My query is that if I am strapping every joist, do I have to install wall straps also?

I see some call for these at a max of 2m between each. The drawing doesn't mention them, and I was initially going to install both for belts & braces, but wanted to check what the experts think!

Once again thank you for taking the time to help!

Will

 

[^woody^]

Flat roofs have joists not rafters!

Also, flat roofs do not need wall plates.

If you are putting joists on wall plates then you would strap the joists not the plate. Work on 2m spacing so that may be every 3rd or 4th joist with twisted straps and no less than 1200mm of strap on the wall with a fixing in every block course ie 225mm spacing.

 

[Backlash187]

Hi, thanks for your reply. Sorry wrong terminology used regarding joists/rafters (slap on the wrist for me lol). The drawing clearly details and describes a wall plate. Also as stated above (and attached as image) the drawing calls for every joist to be strapped. Might be excessive on the architects part??? I wasn't sure if a strap was required on the wall plate as well as each joist. The first part of you reply "If you are putting joists on wall plates then you would strap the joists not the plate" sorts this question. Much appreciated for taking the time.

Will

 

[^woody^]

It's poor design. Likewise the excessive joist strapping specified.

However, your drawing shows a timber frame! Is that what is there, or masonry?

It won't matter, but it's excessive and unnecessary. No plate and less straps is still b/regs compliant.

 

[Backlash187]

Excessive.....great.....just my luck lol. It is single course masonry and stud wall with 25mm gap. Happy days, thanks again for your help/advice woody, much appreciated.

Will