How to fit corrugated roofing sheets
Updated: 23 October 2026
You have a shed or a kennel, a pack of short galvanised sheets, and a morning that goes wrong if the first screw lands in the wrong part of the wave or you step onto the old covering. How to fit corrugated roofing sheets is a sequence: stay off the roof, lap the sheets, then fix the part of the profile you unboxed. The [corrugated sheets comparison](/hub/diy-supplies/corrugated-sheets) is the product table. Peter F., editor for DIY supplies, followed HSE and two UK steel-sheet guides, compiled on 20 October 2026. This is not a laboratory test. A qualifying purchase can earn a commission at no extra cost to you.
You have a shed or a kennel, a pack of short galvanised sheets, and a morning that goes wrong if the first screw lands in the wrong part of the wave or you step onto the old covering.
You have a shed or a kennel, a pack of short galvanised sheets, and a morning that goes wrong if the first screw lands in the wrong part of the wave or you step onto the old covering. How to fit corrugated roofing sheets is a sequence: stay off the roof, lap the sheets, then fix the part of the profile you unboxed. The corrugated sheets comparison is the product table. Peter F., editor for DIY supplies, followed HSE and two UK steel-sheet guides, compiled on 20 October 2026. This is not a laboratory test. A qualifying purchase can earn a commission at no extra cost to you.
Our top picks
| Badge | Product | Thickness | Fixings | Pre-drilled | Note | Price | Offer |
|---|---|---|---|---|---|---|---|
| Best overall |  Harbour Housewares Harbour Housewares 14 anthracite sheets | 0.25 mm | Not in the bullet list; one review cites about 85 bolts | No, listing says none | 9.2 | about £57.99 | View offer |
| Best value |  Mondeer Mondeer 14 dark grey roofing sheets | 0.25 mm | Not in the included-components line | Bullets say no; one review says yes | 9.0 | about £53.99 | View offer |
| Alternative |  Warmfay Warmfay 24 black sheets with screws | 0.25 mm | 400 screws and washers claimed | One review says not pre-drilled | 8.0 | about £73.99 | View offer |
On this page
Stay off the sheet
The Work at Height Regulations 2005, regulation 6, put the order in plain terms. Avoid working at height where you reasonably can. Where you cannot, prevent a fall. Where you cannot prevent it, minimise the distance and the consequences. HSE tells you to treat every fixed roof as fragile until a competent person says otherwise. Corroded metal and fibre cement, including old asbestos cement shed sheets, fail under a foot. Do not walk the new sheets, and do not walk the old bolt line.
If you can reach the eaves from a tower or a tied scaffold, do the job from there. If the only way up is to stand on the sheet, stop.
Lap and pitch
Cladco's corrugated guide uses a minimum pitch of about 10 degrees, a side lap of at least two corrugations, and an end lap of at least 250 mm. Cardinal Steels asks for at least one profile side to side and recommends an end lap of at least 200 mm. Those numbers disagree. Follow the sheet in your hand, and do not blend the two guides into a third system.
If your shed is flatter than about 10 degrees, a harder lap will not turn it into a steel roof. Pitch and the England limits are on corrugated sheets for a shed roof. Lay the first course square to the eaves, or later edges go saw-toothed. Start at the eaves, away from the prevailing wind, so the side lap faces away from the weather.
Where the screw goes
Crest fixing is the usual instruction for sinusoidal sheet. The screw passes through the top of the wave, with a seal washer, into the timber. Some trapezoidal guides say fix in the trough. Mondeer's listing describes trapezoidal grooves. If the profile in the box is trapezoidal, do not force a round-corrugation rule onto it. Stop turning when the washer spreads, not when the sheet dimples.
These packs do not give a trustworthy screw count. Bullets and one review disagree on pre-drilled holes. Drill after the sheet is held square. Bring self-drilling screws with seal washers, and try one in a scrap first. Why kit screws are not a reason to choose the dearest pack is on best corrugated sheets.
Order of work on a small shed
Count the sheets and look for bent corners before you climb. A roof without a ridge cover leaks at the apex. Mondeer's included line is fourteen sheets, and Harbour sells caps separately. Fetch the ridge before the sheets go up.
Set the first sheet square to the eaves, on the end away from the prevailing wind. Lap the next sheet by the one or two corrugations you settled above. The upper sheet covers the lower one at the end lap. Work towards the ridge. These 0.25 mm panels kink if you lever them. Cut only while the sheet is supported.
Look up from the ground for a saw-tooth eaves and for crushed washers. If the old covering looks like fibre cement, or anyone sleeps in the building, hire someone.
Common questions
Do you screw through the crest or the trough?
Sinusoidal sheet is usually fixed through the crest, with a seal washer, so water runs in the trough below the hole. Trapezoidal profiles sometimes specify the trough. Mondeer's listing describes trapezoidal grooves, so match the profile you unboxed. Cladco and Cardinal describe crown fixing for their own corrugated systems. Their screw lengths are not a universal size for a 0.25 mm amazon pack.
How much should the sheets overlap?
Cladco asks for at least two corrugations at the side and at least 250 mm at the end, on their own sheet. Cardinal asks for at least one profile and recommends at least 200 mm at the end. Use the figure that matches the sheet in your hand. On a 110 cm panel that end lap is a large share of each sheet.
What pitch do UK steel-sheet guides treat as the minimum?
Cladco's corrugated installation uses about 10 degrees for their steel sheet. Felt sits on shallower falls. A felt shed that is flatter than that is a poor candidate for these packs. Bitumen sheet uses a different, often lower, pitch table. Do not import that table onto galvanised steel.
Can you stand on the sheets to fit them?
No. HSE says treat the roof as fragile until a competent person says otherwise, and names corroded metal and fibre cement. Do not walk the sheets or the bolt line. Work from a platform that can span the supports. If you cannot arrange that access, the fit is no longer a DIY morning.
What if the pack has no ridge and the screws are poor?
Leave the sheets on the ground until the ridge is in hand. Mondeer does not include one, and Harbour sells caps separately. If the supplied screws strip or are too small, as reviewers reported on Harbour and Warmfay, use your own self-drilling screws and seal washers. Keep any sound washers and discard the soft heads.
Which way do you start, relative to the wind?
Start at the eaves, on the end away from the prevailing wind, so each side lap sheds wind-driven rain. Cladco's guide uses that order, and it tells you to set the first sheet square or the eaves finish saw-toothed. On many UK sheds the wet wind is from the south-west, but check the site.
When should you stop and call a professional?
Stop if the old roof may be asbestos cement, if anyone sleeps in the building, if the timber is rotten, if the span is not a small shed, or if you cannot work from a proper platform. Regulation 6 still applies on a garden building. A 0.25 mm pack does not make a house roof into a weekend job.
Related pages
Sources
Public UK sources and the amazon.co.uk listings compared on this page. Updated 22.10.2026.
- HSE: Fragile surfaces (retrieved 22.10.2026)
- Work at Height Regulations 2005, regulation 6 (retrieved 22.10.2026)
- Building Regulations 2010, Schedule 2 (retrieved 22.10.2026)
- Planning Portal: Outbuildings (retrieved 22.10.2026)
- Cladco: Corrugated sheets (retrieved 22.10.2026)
- Briarwood: 13/3 declaration (retrieved 22.10.2026)
- GWP: Corrugated board grades (retrieved 22.10.2026)
- GWP: What is Correx (retrieved 22.10.2026)