Garage Roof Replacement Harrow

This job came in after the garage roof at a property in Harrow had completely collapsed. The customer wanted the work sorted before winter set in and had seen one of our current offers, so the timing worked well for both sides. It's the sort of job we're called out for fairly often at this time of year, when people start thinking about what their roof will and won't cope with over the colder months.

Our team went in to assess the structure first, since a full collapse usually means there's more going on underneath than just the covering. Sure enough, there was damage to the timbers and decking that needed addressing before any new covering could go down. Skipping that step is how you end up with a roof that looks fine for a year or two and then fails again, so we replaced what was needed and made sure the deck underneath was sound before moving on.

Rebuilding from the deck up

Once the structure was sorted, we fitted 18mm OSB boards across the full 100 square metre area to give a solid, even base. On top of that went a three-layer torch-on felt system: two layers of underlay followed by a mineral finish in charcoal. It's a build-up we use often on flat garage roofs because it holds up well against standing water and general wear, and the finished charcoal felt sits neatly against most brickwork and fascia colours.

We also fitted insulation as part of the flat roof build-up, which makes a real difference to a garage that's used for anything beyond storage, and improved the ventilation to help manage moisture within the roof space. Good airflow matters just as much as the covering itself when it comes to how long a flat roof lasts.

Flashing, gutters and finishing details

Lead flashing and valleys were fitted where the roof met the surrounding structure, which is one of the more common failure points on flat roofs if it's left out or done poorly the first time round. We also fitted new UPVC fascias while we had access, along with UPVC door panelling, which the customer added to the job once they saw the rest of the work coming together. It's a straightforward addition when the roof's already open and access is already sorted, and it meant the garage was dealt with in one visit rather than two separate call-outs.

The whole project, from removing what was left of the old roof to finishing the fascias and panelling, was completed in two days. Given the roof had fully collapsed, it wasn't a light job, but the timescale reflects how the work was planned out before we started, rather than working things out as we went.

Building regulations and paperwork

This particular job didn't need building regulations approval or sign-off, which is fairly typical for garage roof work of this scale, though it's always worth checking with your contractor at quote stage rather than assuming either way. Every job we take on is covered by public liability insurance, and this roof comes with a 10 year guarantee, so the customer has that peace of mind heading into winter and well beyond it.

The result

Compared to where things started, with a roof that had given way completely, the finished job is a complete change. The garage now has a solid, insulated flat roof with proper flashing and ventilation, new fascias, and a tidy UPVC door to match. For a job that began with a collapsed structure, it's now built to handle whatever the Harrow weather throws at it for years to come.

If you're dealing with a garage roof that's on its way out, or one that's already given up, get in touch for a free, no-obligation quote. We'll tell you honestly what needs doing and what it'll cost, with no pressure either way.