I've been asked to help out a relative with some wiring, and have discovered a possible problem.
The roof is a trussed construction and the joists (I'm not sure whether they're called roof joists or ceiling joists?) measure approximately 135mm x 35mm.
One of them has been drilled from below with a 19mm drill, approximately 80mm up through the joist (my relative thought he was drilling into a batten which was used purely to secure the plasterboard - most other rooms have these, but it turns out it was actually one of the joists within the loftspace).
My concern is this hole is about half the width of the joist and goes 2/3 of the way through it vertically, which will obviously weaken the joist significantly.
My questions:
1) How much of a structural aspect do the roof joists perform? I understand they are partially in place to stop the two sides of the roof "spreading" apart but what other structural part do they play?
2) Is this hole a massive concern? If so, what should I do about it? Can I attach some nail plates over the area to hold the joist together just in case the worst should happen? Or can I bolt another joist alongside it? If so, how long should this be and how should it be attached?
Thanks in advance
The roof is a trussed construction and the joists (I'm not sure whether they're called roof joists or ceiling joists?) measure approximately 135mm x 35mm.
One of them has been drilled from below with a 19mm drill, approximately 80mm up through the joist (my relative thought he was drilling into a batten which was used purely to secure the plasterboard - most other rooms have these, but it turns out it was actually one of the joists within the loftspace).
My concern is this hole is about half the width of the joist and goes 2/3 of the way through it vertically, which will obviously weaken the joist significantly.
My questions:
1) How much of a structural aspect do the roof joists perform? I understand they are partially in place to stop the two sides of the roof "spreading" apart but what other structural part do they play?
2) Is this hole a massive concern? If so, what should I do about it? Can I attach some nail plates over the area to hold the joist together just in case the worst should happen? Or can I bolt another joist alongside it? If so, how long should this be and how should it be attached?
Thanks in advance