
At G&M, we use steel box profile roofing on the majority of our buildings. We love steel box profile because it provides us with a durable and long-lasting roofing solution that’s essential for our timber buildings.
Should I have a Steel Box Profile Roof on my Shed?
If your Shed is Pent or Apex with a depth over 4 metres, then yes. Felt isn’t enough to keep the rain out. Steel box profile is our swear-by answer to big roofs and low pitches.
A Pent shed is sometimes called a mono pitch or a lean-to or ‘kind of flat with a run on it…’ An Apex roof is sometimes called an A-Frame or ‘a pointy roof like your house…’
What is a Steel Box Profile Roof?
The type of Steel Roof we use is Permaroof, from Planwell in Morayshire. They offer 3 types of Steel Roofing and we tend to stick with the Nova, unless otherwise requested. The 0.5 Nova (painted finish – 20-year guarantee) is what we choose to cover our Shed, Garage and Garden Room roofs.
Why do you need a steel roof? What’s wrong with felt?
There is nothing wrong with felt; it works incredibly well. However, if the length of a roof exceeds 4m, we believe the rigidity of the felt is no longer capable of carrying its weight, making it susceptible to sagging, which in turn leads to leaking joins.
In 2013, we experienced a high volume of feedback relating to Pent sheds leaking and a fair few big builds too. This was an incredibly testing time for us, we were continually snagging, sealing and re-felting. Our persistence was futile! A shed pandemic! We had no option but to ditch the felt and find an alternative. We had used Steel Box Profile on our bigger projects for years; we knew that because of its proven track record, 20-year guarantee and a 40-year life expectancy, it wouldn’t let us down. Steel cannot experience water ingress, no matter how long the rain batters on.

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What about condensation, Steel is bad for that surely?
It’s not just Steel you know… We still use our sarking boards (roof cladding; tongue and groove boards which face in the interior of your Shed). The Steel is battened on top of the sarking and this provides a cavity allowing any moisture build-up to be ventilated. Not only that we wash our buildings internally with an Anti-Fungi treatment to ensure they are protected from persistent damp conditions.
Is a Steel Roof really what I’m looking for?
It depends on your own preference of how you want your building to look. If your building is a Summerhouse or Cabin, Steel might not be for you as it’s sometimes seen as quite an ‘industrial’ roofing option.
Ideal for Garages and Workshops, but maybe not aesthetically pleasing for other builds. An alternative to Steel, in this case, would be Shingles. We use Isola Shingles on some of our Radiata Garden Room models, which work perfectly.
Not Ideal for a Pent style, but definitely a comparable option for large Apex styles when looking for a little more… Finesse!









