Drilling and Notching Joists

[RobFurn]

I'm converting my garage, The roof is flat supported by joists. I'm putting in celotex between the joists whilst leaving a 50mm air gap. Im venting from one side only as the building inspector said not to bother venting at the abutment just drill through the joists to provide cross venting the problem is I cant drill in the centre of the joists as the following link suggests as the celotex is in the way. My question is can I put in notches (in the correct zones) in the top of the joists hard up against the OSB or do notches only apply to floor joists. Don't want the roof caving in!


http://www.luton.gov.uk/Media Libra...ng/Building Control/ 1 Limits of drilling.pdf

 

[theoldun]

As long as you are in your permitted zones, drill 4 to 6 20mm holes with angle drill in top of joist and knock out the waste between with chisel. Is fiddly job, but when done is same as notch and complies.
If your joists are level you should have firrings on top of joist for fall to roof. Do them in firrrings where you can. Guidance only. old un