Bolting through blockwork

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I have a solid blockwork wall about 2m long that needs a new floor structure installed to both sides. Can I bolt 2 ledger boards to pick up the joists through the blockwork. I was thinking this would leave more of the block intact rather than drilling for resin anchors to both sides so twice as many holes.

Is this common?

 

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Any views on this? I plan to start it next week

 

[^woody^]

Bolt as above.

For damp protection, yes a barrier between the wall and timber it's required, but you'll need to ensure that the timber does not breach the wall DPC. Often, timber floor surfaces are higher than the wall DPC and if this is the case, the timber will need to be packed out from the wall as it will be too late to detail the wall DPC differently. All timbers should be treated.

 

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Thanks Woody.

The ledger board will bridge over the wall DPC. If i fix a DPM to the back of the ledger board will that be ok or does it need to be set off the wall.

Sorry for being dumb but i am not seeing the theory of setting it off the wall if you have a dpm behind the board.

 

[^woody^]

A barrier will protect the timber, but as its tight on the wall, moisture could move upwards past the DPC by capillary action. Hence the requirement for a gap between the wall and the timber

 

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Ok. How much of a gap and is that a must? How is the gap formed?