Fixing into concrete block

[trevorbayliss]

I am making a big shed base at the moment and my foundations are small pads of concrete with a foundation block cemented on top. These blocks will be mostly in the ground.

So the block will be damp. I intend on screwing a base baton of treated timber to each line of pad stones. I will then screw my new floor frame onto these timber beams.

Do you know if masonry frame fixings could be used to hold the base timber plates down onto the foundation blocks ? Or do i really need to use stainless steel fixings.

I would like to use these things in the link because you don't need a plug as they just bite into the concrete.

https://www.screwfix.com/p/easydrive-countersunk-concrete-screws-7-5-x-120mm-100-pack/9008h

 

[Fred61]

That is exactly what I would use without question. Drill a clearance hole in the timber first as this fixing doesn't like to pull things up and will easily strip its grip on the block. I would put a damp proof membrane between the wood and the block as this will help keep the timber dry. Fred.

 

[John D v2.0]

Generally gravity should do the job shouldn't it, not sure you'd screw through the dpc normally. You could strap them down if you were worried about high winds but I'd be reluctant to have a penetration in my dpc somewhere enclosed.

 

[^woody^]

Sheds don't need bolting down.

Avoid having timber permanently damp or in the ground.

 

[trevorbayliss]

Ok, but my thoughts are the block will be in the ground and surround by gravel, so well drained. I will lay a dPC under my first timber bearer and this will sit on the block and proud of the earth. The actual frame for the floor will then screw into these bearers. All wood will be treated and i am sure minimum moisture content will travel up the screw and damage the wood.

 

[John D v2.0]

Fine, but remember that treated timber is only treated on the outside, so if you drill, it isn't treated inside the hole