Advice on soffit / fascia construction

[GCarnegi]

I'm installing new soffits & fascias from scratch to an extension we are doing just now, and am wondering if there is a particular way they are normally constructed. Soffit depth would be approx 200mm.

Intention is to have 6x2 rafter ends cut vertically then a 25x200mm softwood fascia nailed on to the rafter ends with 50mm above the top of the rafter (allowing for 25mm of sarking board and 25mm kick for the eaves course). Does the softwood fascia screw directly to the rafter ends, or should there be any heavier timbers in-between the rafter ends. (pieces of 4x2 for example)?

2x2" timber screwed onto the outside face of the blockwork right at the top (under the rafters) such that some 9mm marine ply can be nailed up from below, with the ply behind the fascia, rather than the fascia on top of the ply, right? I'm assuming I need to bore a 70mm (approx) hole between each pair of rafters (every 600mm?) and fit one of those circular plastic vents. Is that right?

 

[noseall]

The fascia board is fixed directly into the rafter ends. No need for any noggings betwixt rafters.

In 't olden days the fascia would be rebated or routered so that the soffit board notched into the back of the fascia. Otherwise allow the fascia enough drop to allow the ply soffit board to butt against it.

Make sure your fascia is nice and straight i.e. take care when trimming off the rafter ends, otherwise it will show up when fitting the soffit.

You will need more than 25mm kick for the first course of tiles. 40-50mm is more like it. If you can't find any fascia deep enough then fix over-fascia vents on top to give you the extra kick and solve the soffit venting issues in the process.

We normally finish the final course of masonry so that the soffit board sits on top of this final course. It is then a case of allowing the soffit board to sit on top of the masonry by the full width of the masonry usually 100mm. You can then fit trapping timbers to the side of the rafter down onto the top of the soffit board. Using the rafter off cuts usually does the trick as these already have the right pitch cut.

Your method sounds ok so long as you can get a decent fixing into the masonry. You can supplement the fixing by adding some timber 'straps' from the side of the rafter down to your 2" x 2".

 

[Alastairreid]

Your fascia can be fixed to the end of the rafters without any additional reinforcing.

I prefer over fascia vents rather than the discs.

You should fit a timber fillett at the back of the fascia to prevent the felt sagging behind and water ingress should you have any problems with the roof in the future.

Are you fitting eave trays?

Everything else sounds fine to me, good luck.

Beat by noseall..........again

 

[WestmidsChippy]

fixing soffit to the masonary