Attach bearing beam etc. in concrete hollow blocks

[DrKassler]

Hello!

I am planning to build a terrace over the moat that has formed at the back of our house after we removed the soil from the basement section of the house.

The support beam is 225x45 and 8 meters long. The beam will be supported by vertical 45x95 studs screwed into the house wall approximately every other meter. These will stand on the concrete base that exists on the foundation.

First, should there be asphalt felt or similar between the pressure-treated wood and the coated concrete block wall?

Second question, what plugs and screws should I use? 8mm plugs, is that sufficient? Hardly, right?

The beam just holds the terrace against the wall, but still...!

Sincerely,
/Christian

 

[DrKassler]

After reading the fastening manual from Fischer, it became nail plugs, 100 mm long and 8 mm thick. Should work fine in concrete block and carry 60 kg each in concrete, so say 40-50 kg in concrete block then maybe..

That will be fluckert!

/C

 

[imported_Byggaren]

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First, should there be asphalt paper or something similar between the pressure-treated wood and the plastered concrete block wall?

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It doesn't make a difference whether you place asphalt paper in between. I assume, like everyone else, you place the rule/support flush against the wall and tighten the screw properly so the rule is pressed firmly against the wall? In that case, you've only gained the moisture contact surface equivalent to the thickness of the asphalt paper against the rule.

A better option is to get some pieces of flat iron as spacers or, even better, a strip of thick plastic and cut it into pieces to create an air gap between the wall and the rules. This gives the wood a chance to dry out between the rains. A thickness of 5 mm is enough for it to work.
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Byggaren

 

[pbengtsson]

After reading the installation manual from Fischer, it became nail plug, 100 mm long and 8 mm thick.
/C

I used Fischer myself (FUR 10x160 T). These were completely excellent in concrete hollow blocks, no problem getting them really tight. + you can unscrew them.
100mm sounds a bit short if the beam is 45mm, then there's only 55mm left to the wall. But if it's the FUR plug, it should work.

 

[DrKassler]

So air gap is good even if it's pressure-treated wood?

I was looking for FUR-plug but the only useful thing they had at K-rauta was nail plug... :-/
Now the nail plug fits concrete hollow blocks according to the packaging, so I think it'll work anyway. And an insertion of 55mm is sufficient according to the instructions, though it will be less if I'm going to use spacers as well.
Hmm...

 

[Alej]

I am also in need of fastening in hollow lecablock. I tried a facade plug but it doesn't hold. What is recommended for fastening?

 

[Mattias_Eson]

Anchor mass. Drill and fill the hole, push/pull the screw and let it cure. Use a good caulking gun (and strong forearms) I think Fischer's anchor mass works well. For Hilti's, you must have a special gun. Use long French screws.

 

[Andreas Blomkvist]

Which dimension did you use? Also had problems but with 175mm long ones it went well. Attach the 14m support beam to the facade.

 

[Alej]

I found a screw with a plug from hilti, it pulled like crazy