Cut into the rafter

[Hotivar]

Hello!

Despite all the warnings, I managed to saw about 4 cm into a rafter when opening a hole for an attic hatch in the garage.
How do I best repair my mistake?

 

[andersmc]

It depends on how and where the cut was made. If you can provide a picture, you'll likely get better assistance. But a general tip is to get a spikplåt/hålplatta and attach it with ankar screws over the cut.

 

[Hotivar]

This is what the cross-section of the roof truss looks like.

 

[Mats]

Would place a metal connector plate on each side and then a number of anchor screws on each side. It's also one of the braces for the truss and not one of the outer parts, right?

 

[Hotivar]

That's right, it's one of the stages.

Thank you for the help.

 

[imported_Byggaren]

Does it appear to be the drawn strut from the ridge down to the lower frame in a W-truss?

If it is, it is essentially subjected to tensile forces. Then you can calmly do as mats_o and andersmc suggest, apply a patch over the weakening p.b.s.

But I suggest you avoid nail plates and use a couple of 12 mm K-plywood patches instead, fastening them with glue and through bolts. If you make them long enough, say 30-40 cm, you'll get a good grip for both glue and screws. The latter should be concentrated towards the ends, not at the weakening. For glue, you can use a PU glue for construction purposes since the strut is rough-hewn. Otherwise, take an electric hand planer and smooth it evenly on the surface that will face the K-plywood.
______________
Builder

 

[Hotivar]

Yes, that's correct, the truss looks like a W and it's the brace from the ridge to the bottom chord that is damaged.

I could combine the suggestions, first gluing on the K-Plywood and then screwing on 30 cm hole plates. It seems sensible to screw a bit away from the cut, otherwise you might weaken the brace further.

 

[snickarboden]

Personally, I would have used plywood, regular outdoor wood glue, and regular wood screws.

/Kent

 

[daniellindholm]

I absolutely agree with the builder about plywood. You can, if you want, just to sleep extra well, glue wood into the cut as well, but that's overkill if you put plywood on the sides that you both glue and screw.