How to attach a patio roof to side of house?

curriedogg73

Hi I am about to build a roof over a deck. It is 5.4 long 2.7 out from the house it is being built in timber h3 190x45 rafters 90x45ontop of rafters 190x45head n back board. With four post bein extended to 2.5 above the deck. I am needing to no wat size  screws to attach the board to the existing eve n do I need some sort of flashing. Also wat size screws for rest of construction

MitchellMc

Welcome to the Bunnings Workshop community @curriedogg73. It's a pleasure to have you join us, and many thanks for your question about connecting a patio roof.

It's important to know that you can't fix your new roof directly to the eaves, as eaves are not structural—they're just an overhang made of lightweight timber and fascia, and they’re not designed to carry any load. To securely attach your patio roof, you'll need to fix it into the structural framing of the house, such as the rafters or trusses behind the eaves. This typically involves removing some roofing material—either tiles or metal sheets—so you can locate the structural roof members and connect into them properly. You may need to use Roof Extenda MKII Brackets or a ledger board that’s bolted through into those members. For that connection, you’d normally use M10 or M12 coach screws or structural bolts, spaced according to engineering guidelines.

You’ll definitely need flashing. Flashing is important to stop water from getting in where the patio roof meets the house. Usually this involves an L-shaped flashing that tucks under the existing roofing material and laps over the new patio roof to direct water away.

For the rest of your timber construction, such as fixing rafters and battens, bugle batten screws around 100–125mm long are commonly used. For larger timber-to-timber joins like beams to posts, galvanised coach screws or structural bolts are often the go-to. Make sure all fixings are rated for outdoor use and comply with building standards. If you're unsure about any of this, especially with load-bearing parts, it's well worth having a chat with a builder or structural engineer to make sure everything is done safely and to code.

Please let me know if you have any questions.

Mitchell