Flat roofs in the Lea Valley, from Ware to Enfield

Where are flat roofs found on local homes?

Most houses between Ware and Enfield have a pitched main roof, but flat roofs turn up in plenty of places around them. Rear and side extensions, garages, porches, box dormers on loft conversions, bay windows and the back additions of older terraces often have one. Some 1960s and 1970s houses and flats were built with flat main roofs.

A flat roof is never completely flat. It has a slight fall, so water runs to a gutter or outlet rather than sitting on top.

What are the signs of a problem?

• water coming through the ceiling below, often after heavy rain
• puddles that stay on the surface for days after rain
• blisters, splits or cracks in the covering
• lifting or open seams at the edges and joints
• moss, plants or debris collecting in low spots
• a soft or springy feel to the deck, which the roofer will check rather than you

If water is coming in, keep off the roof, catch the drips and keep clear of a sagging ceiling. Take photos for your insurer and then send an enquiry. We cannot promise when a roofer will be free.

What materials are used?

There are three common coverings, each with its own way of being laid. A roofer can explain which suits your roof.

• Felt: layers of reinforced bitumen membrane, bonded to the deck and to each other. Many systems are torched on with a gas flame, and some are bonded cold or with adhesive. Felt has been used on British flat roofs for a long time and many roofers fit it.
• EPDM: a synthetic rubber membrane, often laid as a single sheet and bonded to the deck, with trims round the edges. It is laid cold.
• GRP: glass-reinforced plastic, often called fibreglass. Resin and glass matting are laid over a timber deck and finished with a top coat, which cures into a seamless surface.

Each material has its own strengths and limits depending on the shape of the roof, how much it is walked on, the details round upstands and roof windows, and the roofer's own experience. It is worth asking why a roofer recommends one over another for your roof.

Repair or replace?

A small split or a failed seam can often be repaired. If the covering has failed in many places, if water has soaked the deck, or if the roof is ponding badly, replacing the covering, and sometimes the deck beneath, may make more sense. The roofer will look at the condition of the decking and joists before deciding.

Do the Building Regulations apply?

They can. Re-covering a flat roof does not normally need a building control application if the work affects less than half of that roof and less than a quarter of the whole building envelope, meaning the walls, floor, roof, windows and doors together. Beyond that, or if the new covering is 15 per cent or more heavier than the old one, the work becomes notifiable, and the roof may need extra insulation to meet current standards. The roofer may be registered with a competent person scheme that lets them self-certify, or they can apply to building control. The Planning Portal's page on work to an existing roof sets out the tests.

Does planning permission come into it?

Re-covering an existing flat roof on a house rarely needs planning permission. Flats, listed buildings and homes covered by an Article 4 direction are the usual exceptions. A new extension or dormer with a flat roof is a separate question about the building work as a whole.

What about fire and safety?

Hot works, such as torching on felt, carry a fire risk, especially near timber, roof windows and the eaves. Ask the roofer how they manage it. Safe access and edge protection while they work are the roofer's responsibility.

What details help with a flat roof enquiry?

• your postcode
• what the flat roof covers, such as an extension, a garage or a dormer
• its rough size, if you know it
• the current covering, if you know it, and roughly how old it is
• what has gone wrong, with photos if you can take them safely
• whether you can reach it from a window or a lower roof