A frequent question that we are asked at Minera Roof Trusses is, “Can I drill holes in my trusses/ joists?” Most commonly, we’re asked this for plumbing and electrical reasons such as fitting pipes and wiring through the trusses after the holes have already been drilled and it has been picked up by a building inspector on site.
We’re also asked on occasion whether customers are able to cut our trusses/ joists and this has been in cases where plans have changed later down the line in projects, decisions have been made to install a roof light or to cut trusses/ joists to fit into spaces where measurements have altered from what was originally supplied.
The answer to both of these queries is unfortunately, you’re NOT able to do this and we would like to explain why…
The calculations which are provided for you are designed to negate the necessity of a structural engineer (a cost saving for you – you will thank us later) and can be used in their entirety for building control approval. Therefore, any alteration, no matter how small, risks invalidating our designs. Any alterations can negatively impact on the ways in which forces are transferred into the timber and plates.
Put simply, we kindly ask that you do NOT cut, drill or notch your trusses unless otherwise agreed with Minera Roof Trusses. Our metal web joists are also designed specifically to accommodate services in between their webs so there’s really no need to get that saw out. You can find further benefits of using metal web joists here. We go to great lengths during the design phase to ensure your trusses and joists are accurately stress graded and meet with EC5.
If you’re in doubt, we say to always ask us before it’s too late! We’re on hand to help and give the best possible advice during design and for your installation. We will do everything we can to meet your design requirements but making adjustments afterwards that were not intended is a risky business!
Occasionally, it may be possible to carry out a remedial detail on site to the affected roof trusses/ joists by our Engineers but this is only achievable in rare circumstances, cannot be guaranteed and would incur an additional cost from ourselves, not to mention mammoth labour costs on site to reinstall or make adjustments. What a nightmare that would be!
All of the images included in today’s news story are aimed to give you a better idea of situations where our designs have been invalidated due to adjustments being made on site after delivery without consultation. These have not only been costly errors but dangerous mistakes that we wouldn’t want you to fall foul of. All cabling and pipes should be situated in the void spaces at either side of the trusses. If in doubt, please contact us!
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