Cut the trusses to get more space in a garage conversion.

15 Jan 2007
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United Kingdom
Good, now i've got your attention!

I want to convert my double garage (detached from my house) into an office. Parking is not an issue. I will replace one garage door with a smaller UPVC one and brick up the other garage door. Happy with most aspects BUT i want to put a toilet in the roof space and use it for storage but i have standard trusses which of course leave no space.

What is the cheapest way of increasing the roof space to be able to fit a small bathroom and have some space for documents, samples and brochures. Also, i plan to use a spiral staircase to avoid losing too much space below and to get access to the highest point in the eaves (the old 2.0m head height, etc).

One thought has been to put a steel through just below and supporting the ridge board, from gable end to gable end, allowing the struts to be cut. The putting in decent floor joists to stop bulge and adding a few beefier purlins for good measure, what could possible go wrong with that...........???????:cool: :idea:

I know this is a real old chestnut and i have looked through for a similar thread but nothing seen so any advice would be very much appreciated. :D
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You'll need to employ a structural engineer to do a design enabling you to cut the struts out. No other way to proceed if you are doing things by the book! Effectively there will be a steel each side and a structural stud wall to support the remaining rafters which may also need upgrading. There was a thread on here a while ago showing such a conversion albeit a much bigger one although the principle is the same. //
Thanks! Don't like the sound of the supporting wall bit as we had earlier plans to raise the roof by 4' to put in much more usable space upstairs but BC said we would need to sink 2m foundations as there are trees nearby. The existing walls have 1m foundations, have been up for over 25 years and there isn't the tinyest crack to be seen anywhere but what do i know.........

My question would then be, if the existing roof sits fine on a single skin with 1m foundation, would this be classed as a 'supporting wall' for your suggestion or would it need to be beefed up with pillars, etc? I will get a structural engineer but i want some knowledge before i sound out BC and then see an eng for his/her thoughts.

Thanks for your time.
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:D Hi There, we have just had our single garage converted to a study / spare bedroom with a small WC in the corner. We shopped around and in the end used Dracom Builders who had the whole job completed in 2 weeks.

My husband is still kicking himself that he didn't do it himself but was really pleased with the work and the price!!!

Good luck!

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