Commercial Roofing Bournemouth
Roofs over working premises. Warehouses, industrial units, shops, offices and blocks of flats across Bournemouth, Poole and Christchurch, programmed around your opening hours.
The site visit is free and so is the written itemised quote. Thomas Hannen prices every job himself.
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Commercial premises
Commercial roof repairs and flat roofing for business premises
On a big roof the drip inside is almost never underneath the defect. Water gets in at one lap, one split upstand or one blocked outlet, then runs along the deck profile or down a purlin until it finds a way through the ceiling. Chasing the stain across a warehouse floor wastes a day, so we work back from the outlets.
We take commercial and landlord work alongside the housing. The Nuffield and Mannings Heath estates in Poole, the Airfield estate in Christchurch and the older shop parades along Christchurch Road are all inside our normal working area. Free site visit, free itemised written quote, and Thomas Hannen prices every job himself.
The roof is part of the business, not just the building
A domestic leak is an inconvenience. A leak over a racked aisle, a server cupboard or a shop floor is stock and downtime, so the first visit is about stopping it. Solving it beautifully comes after. We sheet, seal or patch, then come back with a written scope once we have found the cause.
Pitched and domestic work sits on our roofing services page, and there is another for our roofers in Poole.
Premises we work on
Warehouses, units, shops, offices and blocks of flats
Commercial roofs here are warehouses and industrial units, shops and parades, offices and mixed use buildings, and blocks of flats. Each has its own weak point, and not one of them looks like a house roof.
Warehouses and industrial units
Profiled sheeting, valley and box gutters between the bays, rows of rooflight panels, often a flat roofed office on the front. Warehouse roof repair is mostly gutter lining, lap sealing, fastener replacement and rooflight swaps, worked from a platform, never by walking the sheets. On a unit built before 2000 we establish what the sheeting is first.
Shops and retail parades
Behind a smart shop front sits a small flat roof, a parapet, a box gutter shared with next door, and a rear extension in felt last touched decades ago. The party gutter is a frequent source of leaks on a parade, because two people own it and neither clears it. We sequence the work so the shutters still go up on time.
Offices and mixed use buildings
Larger single ply or asphalt roofs, air handling plant on plinths, cable and pipe penetrations, access hatches. Every penetration is a joint, and a roof that has had two rounds of plant has had two rounds of holes cut in it. We form proper collars where somebody once ran sealant.
Blocks of flats and communal roofs
Shared coverings on flat roofed blocks and mansard conversions, with a service charge and a managing agent behind them. The structure belongs to the freeholder, so whoever sees the stain is rarely the one who can order the repair, and past the statutory threshold per leaseholder there must be a consultation under section 20 of the Landlord and Tenant Act 1985. More on that on our Bournemouth and Christchurch pages, and on our page for landlords and managing agents.
Flat roof coverings
How do single ply, EPDM, felt, asphalt and GRP commercial roofs fail?
Commercial flat roofs are laid in single ply, EPDM, felt, asphalt or GRP, and each gives up in its own way. Which one you have decides whether the answer is a repair, an overlay or a strip and re-cover, and an overlay over wet insulation is wasted money.
| Covering | Where you find it | How it fails |
|---|---|---|
| Single ply membrane | Modern units and office blocks | Welded laps opening, fasteners pulling through, shrinkage at the upstands |
| EPDM rubber | Simple roofs, few penetrations | Bonded seams and corner details rather than the field of the membrane |
| Built up felt | Older shops, offices, blocks of flats | Blistering, splitting at the laps, the cap sheet losing its surface |
| Mastic asphalt | Period commercial buildings | Crazing, cracking over movement in the deck, failure at the skirtings |
| GRP fibreglass | Canopies and anything walked on | Hairline cracks where the deck below moves, thin laminate at the trims |
Ponding, falls and the things at the edges
A flat roof is not flat. It is built with a fall so water leaves it, and water still lying there two days after the rain says the fall has gone, the deck has deflected, or the outlet is not working. Ponding does not cause a leak. It finds one, sits on it and freezes in it until the covering gives up.
Outlets and gutters come first. They block with leaves, moss and sand, and the overflow then becomes the parapet, the door threshold or the ceiling below. Box and valley gutters are worse: long, taking the whole roof, and once the joints or the lining fail the water enters at the eaves. Lining one in place beats replacing it.
Then upstands, flashings, roof lights and edge trim. An upstand needs enough height that ponded water and driven rain cannot get over it, with a cover flashing chased into the wall rather than mastic across the top. Roof lights leak at the kerb far more often than through the panel, and the trim, drips and copings take the wind.
Leak tracing
How do you find the leak on a commercial roof the size of a warehouse?
A leak on a warehouse roof is found by working back from the outlets, not out from the stain, and by hose testing section by section. Water can enter twenty metres from where it comes out.
- Outlets, sumps and gutter joints cleared first, because most of it is there
- Every penetration walked: plinths, vents, cable entries, hatches, rooflight kerbs
- Sections hose tested in turn so the entry point has to show itself
- Boards lifted where the insulation feels heavy, because wet boards move water sideways
- The underside read from inside: purlin runs, deck laps, where the drip starts
- Dated photographs of the defect itself, to send the landlord or the agent
Working round you
Can the unit stay open while the commercial roof is being done?
Yes. Nobody closes a warehouse for a roof. Access, deliveries and which areas stay in use are agreed at the survey, before a date is booked.
Access worked out first
Scaffold, tower, cherry picker or mast lift, and where it stands clear of a loading bay or a fire exit. Priced as its own line.
Hours agreed
Agreed before we start, around deliveries, noise and access, so you can keep trading. Scheduled work runs Mon to Fri, 8am to 6pm.
Phased and made safe
The roof comes up in sections small enough to close down the same day. Nothing left open overnight, stock below sheeted.
Handed back with photographs
Outlets tested, roof swept, yard cleared, and a photographic record of the finished detailing for your file.
Quoting and instructing
What moves the price of a commercial roof, and who signs it off?
On commercial work the access and the sequence usually cost more than the covering does. A single ply roof you can drive a mast lift up to, and the same roof over a yard of pallets that has to be done in four phases around deliveries, are different jobs with identical square metres.
Roof work is work at height, and the HSE guidance on roof work is why a working platform, edge protection and a safe route onto the roof are priced lines rather than optional extras. Fragile rooflights and older cement sheeting change how a unit is approached, and both are settled at the survey, not found on the first morning. The rest is predictable: how much of the build up is wet, how many penetrations and upstands there are, whether gutters are lined or replaced, and how the waste is taken away.
Who can actually instruct the work
Worth settling before anyone measures anything. A tenant on a full repairing and insuring lease may be liable for the roof; one on an internal repairing lease is not. An agent wants a scope that can go out to tender, and a residents' company needs one that survives a leaseholder consultation.
Straight answers
Straight answers about commercial roofs
Who pays for the roof on a leased commercial unit?
Who pays for a leased unit's roof depends on the lease, so read the repairing clause before you instruct anyone. A tenant on a full repairing lease is usually liable for the roof, including the covering, the gutters and the outlets. A tenant on an internal repairing lease normally is not, and the landlord deals with it.
On a multi-let estate or a shop parade, the roof is often kept by the landlord and recharged through a service charge, and a party gutter between two shops may be shared. Whoever is responsible, a leak over stock needs stopping first, so report it in writing with photographs straight away and keep a dated record. For whoever pays, a scope that can be compared or sent out to tender is worth more than a single figure. We give an itemised written quote with photographs, addressed to whoever is actually instructing, whether that is the tenant, the landlord or the agent. To get the leak looked at, book a free site visit.
Should a commercial flat roof be overlaid or stripped?
Overlay it only if the insulation and deck underneath are dry and sound, and strip it if they are wet. An overlay, a new membrane laid over the old one, saves the strip-out and keeps the building watertight while the work is done, which suits a unit that has to keep trading. But wet insulation carries water sideways, stays wet under a new layer, and rots or corrodes the deck while the new surface looks perfect. The way to tell is to open test areas and lift boards where the roof feels heavy or soft underfoot, not to judge it from the surface. Ponding, lost falls and blocked outlets need sorting at the same time, or the new covering sits in the same water as the old one did. Single ply, EPDM, felt, asphalt and GRP each take an overlay differently. Our flat roofing page covers the deck, the falls and the detailing in more depth.
Is it safe to go up on a warehouse roof to look at a leak?
No, not without proper access. Warehouse and industrial unit roofs often have fragile rooflight panels that look solid from above, and older cement sheeting that will not take a person's weight. A fall through a fragile roof is one of the most serious accidents in building work, and the HSE rules on roofwork explain why nobody should walk the sheets without a platform, edge protection or a mast lift. What you can do safely is gather information from inside and from the ground. Note where the drip starts and in which bay, whether it only comes in heavy rain or with wind from one direction, and photograph it with the date. Check the outlets and downpipes you can see from the yard for overflow. That record shortens the job when the leak is traced. On a unit built before 2000, we establish what the sheeting is before anyone goes near it. Book a leak investigation and we work it from a platform.
Why do warehouse box gutters keep leaking?
Because a box or valley gutter carries the water from a whole roof along one long channel to a few outlets, so any fault in it sends water into the building rather than over an edge. The usual causes are failed joints and linings, outlets blocked with leaves, moss and sand, and a gutter that has lost its fall so water stands in it. Standing water finds every split and rusts a steel gutter from the inside. On a shop parade, the party gutter between two units is a common culprit, because two people own it and neither clears it. Clearing and flushing the outlets fixes a blockage. A failing gutter can usually be lined in place with a new membrane rather than replaced, which is quicker and lets the business keep trading underneath. Regular clearing is cheaper than either. Our gutter cleaning page covers outlets, hoppers and downpipes in more detail.
Questions
Questions about commercial roofing
Do you take on warehouse and industrial unit roofs?
Yes. Warehouse roofs are mostly profiled sheet with valley or box gutters and rows of rooflights, often with a single ply or felt flat roof over the offices at the front. We line failed gutters, seal laps, replace fixings and brittle rooflights, and re-cover flat sections.
Can you work around our opening hours?
Ask when you ring: our scheduled hours are Monday to Friday, 8am to 6pm, and on a shop or an office the sequence matters more than the hours: no area of roof is left open at the point you reopen, and anything stripped is made watertight before we leave.
Who instructs roof work on a block of flats?
The freeholder, normally through a managing agent or a residents' management company, because the structure is theirs and it comes out of the service charge. Past the statutory threshold per leaseholder they have to be consulted first, under section 20 of the Landlord and Tenant Act 1985.
The water comes in nowhere near where you say the fault is. How do you find it?
By working from the water backwards. It enters at one lap, outlet or upstand, then travels along the deck profile or down a purlin before it finds a route through the ceiling. We start at the outlets and every penetration, and hose test in sections until the entry point shows itself.
Where we work
Commercial roofing across Bournemouth, Poole and Christchurch
We repair and re-cover commercial roofs across Bournemouth, Poole, Christchurch and Wimborne, from industrial estates to shopping parades and business parks. These are the commercial areas inside our working area:
- Nuffield, Mannings Heath and Alder Hills in Poole
- Riverside Avenue, the Lansdowne offices and the Boscombe parades in Bournemouth
- The Airfield estate and Somerford Business Park in Christchurch
- Cobham Road and the Ferndown Industrial Estate, out towards Wimborne
Free quote
Get a price for your commercial roof
Send the address and a couple of photographs, or book a visit. We will get on the roof, find out what is actually wrong, and put an itemised written quote in front of you.