Asbestos Garage Roof Removal in Guildford

Grey corrugated sheet on a garage roof is the single most common asbestos material we get asked about in Guildford. It is on detached garages in Burpham and Merrow, on the coal stores behind the post-war terraces at Park Barn and Bellfields, and on half the workshops on Slyfield Industrial Estate. It went up between the 1950s and the mid 1980s and a lot of it is still there.

The good news, and it genuinely is good news, is that this is the least dangerous asbestos product in a domestic setting and the cheapest to deal with. The fibres are bound into cement. Left alone and in one piece, a cement roof is low risk.

How to tell whether your garage roof is asbestos

Start with the profile. Asbestos cement sheet has a wide, shallow corrugation, usually about six inches from crest to crest, and a flat grey colour that turns green with moss on the shaded side. Steel sheet has a tighter, sharper profile with square shoulders, and it rusts at the cut edges and around the fixings. Corrugated bitumen, which is what a lot of garages were reroofed with in the 1990s, is thicker, softer and comes in black, green or brown.

Then look at the fixings. Cement sheet is almost always fixed with hook bolts through the crest of the corrugation, with a little dome cap and a rubber washer. If you can see hook bolts and a chalky grey sheet, you are probably looking at asbestos cement.

Age settles most of it. Blue and brown asbestos were banned in 1985 and white in 1999, so anything built or refurbished before 2000 may contain it. A garage that went up with a 1968 house almost certainly does. A garage added in 2004 does not.

What you cannot do is confirm it by eye. Fibre cement made after the ban looks close enough that nobody can tell the difference reliably from the ground, and the only certainty is a sample and a lab test. That is what an asbestos survey is for, at £200 to £400. For most garage roofs it is not worth it: send a photo, and if the answer is obvious we will say so.

What it costs

A single garage roof is £450 to £1,200. A double is £750 to £2,500. Those are indicative and the range is wide because access does most of the work in setting a price.

The things that push it up:

Scaffolding, where the roof cannot be worked safely off a ladder or a tower, adds £300 to £600. Roofs backing onto a neighbour's garden, roofs over a conservatory, and anything above single storey tend to need it.

Disposal by weight, charged at £0.55 to £0.80 per kilogram. A sound sheet and a shattered sheet weigh the same, but shattered material takes far longer to collect and bag, so damage costs twice.

Distance from a hard standing. If the sheets have to be carried forty metres round a house to reach the van, that is time.

The things that do not change it much: the age of the roof, the number of sheets within reason, and whether it is mossy. Moss is normal.

There is a fuller breakdown, including the interior materials, on the asbestos removal cost page.

What happens on the day

The area under and around the roof is sheeted, and anything you have stored in the garage is either moved out or covered. The sheets are damped down. Fixings are cut rather than levered, because levering is what cracks a sheet and cracking is what releases fibres.

Sheets come off whole, one at a time, and go straight into wrapping rather than onto a pile. Anything that does break is double-bagged and labelled on the spot. The frame is swept and the ground under it is checked, because small fragments collect in the gutter line and in the grass at the edge of the slab.

The load goes on a vehicle registered to carry hazardous waste, to a site permitted to accept it. You get a hazardous waste consignment note recording what the waste was, who carried it and where it went. Keep it for at least three years. When you sell the house, that piece of paper answers the question a buyer's solicitor is going to ask.

Can you leave the frame and just take the sheets?

Almost always, yes, and it is usually the cheaper path.

Garage roofs of this era are sheets fixed to a frame, not a monolithic structure. Once the hook bolts are cut the sheets lift off and the frame stays. If the frame is steel it is very often still sound after sixty years, because it was overspecified in the first place. Timber frames are more variable and worth looking at while the roof is off, which is the one moment in the garage's life when you can see all of it.

What goes back on is your call. Box profile steel is the usual answer, and it is quick because it fixes to the same purlins. Corrugated bitumen is cheaper and lighter but has a shorter life. Modern fibre cement looks closest to the original if the garage is part of a matched terrace and you care about that.

We do not fit the new roof. We take the old one away and leave you a clean frame, which is the part that needs the licence-adjacent care. Any roofer can do the rest, and separating the two usually costs less than one firm doing both.

When removal is not the right answer

If the roof is sound, in one piece and you have no plans for the garage, there is a reasonable case for leaving it. Cement in good condition is low risk and there is no legal duty on a homeowner to remove asbestos from their own house.

That changes when a sheet cracks or slips, when the surface starts flaking after frost has got into it, when anything is going to be drilled or screwed through it, or when you are selling and a survey has flagged it. It also changes if you are having solar panels, a loft conversion or a rewire, and a trade is about to be working next to it.

Sealing rather than removing is an option on a sound roof, at roughly £30 per square metre against £50 and up for removal. Encapsulation suits a workshop roof you want a few more years out of. It does not suit a roof that has already weathered through.

One more thing worth knowing if you are selling. A cement garage roof does not stop a sale and it is not a legal defect. What it does is give a buyer something to negotiate with, and the number they knock off is usually larger than the number it would have cost you to deal with it. Having the consignment note in the pack removes the conversation entirely.

What to send us

Three photographs and a postcode is usually enough to price a garage roof properly, and it saves a visit that neither of us needs.

The first is the whole garage from a distance, far enough back that the roof pitch and the surroundings are visible. That tells us the size, the shape and roughly how the sheets are laid.

The second is close in on the roof surface, ideally from an upstairs window if you have one overlooking it. That shows the profile, the fixings and the condition, which is the part that decides whether this is a straightforward job or a notifiable one.

The third is the approach. Stand where a van would park and photograph the route to the garage. Gates, steps, a narrow side passage, a slope, a fence panel that would have to come out. That single picture moves the price more often than the roof does.

Then tell us the postcode and whether there is anything you already know: a cracked sheet, a leak, a neighbour attached on one side, a conservatory below. Everything you say up front makes the quote firmer, and nothing you say makes it worse.

Guildford garages in particular

The town's housing tells you where these roofs are before anyone looks.

The council-built estates at Park Barn, Bellfields and Stoughton went up in exactly the window when asbestos cement was the standard way to roof a garage block or a coal store, and a fair number of those blocks still have the original sheets. The 1930s to 1970s stock at Burpham, Merrow, Onslow Village and Westborough is the classic picture: a detached or semi-detached garage beside the house, shallow-pitched corrugated roof, thirty years of moss, and an owner who now wants a car port or a home office.

Access varies more than the roofs do. A Merrow garage on a wide plot with its own drive is a straightforward morning. A garage at the end of a shared rear access behind a Westborough terrace, where the van cannot get closer than the road, is the same roof and a different price.

We work outward from Guildford across the whole of west Surrey and into north-east Hampshire. The areas we cover page has the town list and the local detail.