Connecting sole plate to block work with Marmox in between.

[SimonD]

10 hours ago, Mr Punter said:

 

I have seen this on a project.  They had some breathable insulation on the outside.  Probably like the Steico stuff.

 

Also, some internal walls have OSB sheathing added for racking strength.

That was the orginal plan for this project - it was designed to have woodfibre insulation throughout. However, the supplier then tried to stiff me on the price, hiking it massively compared to the price given during technical design. I then changed the timber frame design and now we have sheepswool throughout; so it's OSB as internal sheathing that doubles as vapour control and airtightness layer, sheepswool between studs and then I've counterbattened outside the timber frame for additional sheepswool, beather membrane, battens and cladding. Overall it'll perform on a par with the woodfibre and saved me nearly £9k overall on insulation.

 

 

 

[SimonD]

8 hours ago, SeanDean said:

Thanks this cleared it up for me.

 

I have 12mm OSB 3 ply on the outside.

?

[SimonD]

7 hours ago, Mr Punter said:

I would have stainless steel restraint straps externally.  Have the top bent over top of the sole plate and then rum down the outside 500mm and fix to the blockwork with plugs and stainless screws.  Get them 1200 long and cut in half.  Light duty if the engineer says it is OK.

I've got something similar on my current timber frame, although that is sitting on an existing ground floor masonry wall. In our case the SE also specified Tapcon anchors through the sole plate into the masonry but our roof is curved so there's increased uplift.

 

8 hours ago, SeanDean said:

Some really useful responses from you all that have really helped me understand what I need a lot more and the reasons why. 

 

I'm going to work on a solution that includes anchor or resin bolts along with a strap like the one below, I just need a solution for sealing the DPC after it's been penetrated along with sealing the DPM if I put the straps on the inside of the build. Any input would be greatly appreciated.

 

 

 

 I think it would be okay to use resin fixed anchor bolts and then use mastic to seal around the penetrations. In the US, when they're aiming for high airtighness levels, they'll add an EDPM strip to the dpm/dpc layer below the sole plate. The brackets you show above are really just uplift restraints so if you do need additional fixing, restraint straps as @Mr Punter suggests would probably be easier to install.

[Cait]

On 04/03/2021 at 13:56, Mr Punter said:

I would have stainless steel restraint straps externally.  Have the top bent over top of the sole plate and then rum down the outside 500mm and fix to the blockwork with plugs and stainless screws.  Get them 1200 long and cut in half.  Light duty if the engineer says it is OK.

@SeanDean Hi Sean, have enjoyed following this discussion some very useful questions and comments - how's your extension coming on and did you go with the stainless steel restraint straps as @Mr Punter suggested?