A new or repaired flat roof on your Lakenheath property will perform far better and last significantly longer if you understand a few straightforward maintenance habits from the start.
We install and repair flat roofs on garages, extensions and outbuildings using EPDM rubber membrane and felt systems. Both require correct deck preparation, proper drainage falls and properly formed junctions where the roof meets walls or upstands. When any of those elements are right, a flat roof is a reliable and relatively low-maintenance structure. When they are compromised - through poor installation or neglect - water finds its way in and repair costs mount quickly.
Lakenheath homeowners with flat-roofed garages or rear extensions face the same vulnerabilities as anywhere else in Suffolk: ageing felt that becomes brittle, lap joints that open up, outlets that block and flashing that works loose at abutment walls. Most of those problems are either preventable or catchable early if you know what to look for.
On a pitched roof, gravity does almost all the work - water runs off quickly and does not dwell on the surface. On a flat roof, water moves more slowly toward the outlet and in practice often sits in shallow pools for hours or even days after heavy rain. That standing water accelerates membrane degradation, puts stress on outlet joints and, if it finds a route in, travels a long way before showing as a damp patch inside. Regular visual checks catch problems before they become expensive.
A basic visual check twice a year - once in autumn before the wet season and once in spring after it - is enough to stay ahead of most problems. You do not need to get on the roof to do this. From ground level or an upstairs window, look for:
If you have safe access to the roof surface itself, the inspection can be more thorough, but never walk on a felt or EPDM roof in hard-soled shoes - soft-soled footwear only, and avoid putting weight near the edge or near any areas that feel soft underfoot.
A blocked outlet is one of the most common causes of flat roof failure, and it is entirely preventable. Outlets on flat roofs collect leaf debris, moss fragments, silt and anything else that washes across the surface. A fully blocked outlet can cause water to back up across the whole roof area, increasing the load on the membrane and forcing water into any weakness in the joints or flashing.
Clearing the outlet takes five minutes. Lift the grating if there is one, remove any debris by hand and flush the outlet with a bucket of water to confirm it drains freely. Do this at least once in autumn after the leaves have fallen, and again in early spring. If the outlet drains through a downpipe, check that the downpipe itself is clear at the same time.
If water consistently ponds in the same area even when the outlet is clear, the falls may be insufficient or the deck may have settled. That is worth mentioning when you next have a roofer on site - it can often be corrected with a tapered insulation system or lightweight screed before the next membrane replacement is due.
Moss and algae growth on flat roofs is common, particularly in shaded areas. On felt, moss retains moisture against the surface which accelerates degradation. On EPDM, it is less damaging but still worth managing because thick growth can block outlets and make inspection harder.
A proprietary biocide treatment applied according to the manufacturer's instructions is the right approach - not a pressure washer. Pressure washing an ageing felt roof can strip the mineral surface and blast water into lap joints, causing more damage than the moss itself. Treat, let the product work, and brush off the dead growth gently once it has died back.
Do not attempt to cut or scrape moss off a felt roof with tools. The surface is more delicate than it looks, particularly on older felt that has begun to lose its flexibility.
Where a flat roof meets a house wall - on a rear extension, for example - the junction is sealed with lead flashing that is cut into the mortar joint and dressed down over the upstand. This is one of the areas most vulnerable to movement. Thermal expansion and contraction work on the lead over time, and a long run of flashing that was not properly anchored can pull away from the wall at the top.
After a spell of high winds, it is worth checking the wall junction visually from a safe position. If the flashing has lifted, water can run behind it and into the roof structure without appearing as an obvious external leak - you may only notice damp inside some time later. A loose flashing is a straightforward repair when caught early and a much bigger job when it has been allowing water in for months.
If you notice a crack, blister or lifted flashing during your check, the right move is to call a roofer rather than attempt a DIY fix. The reason is not that the repair itself is always complex - it often is not - but that a patch applied incorrectly or with incompatible materials can trap moisture and create a larger failure beneath the surface. DIY sealant over an EPDM membrane, for example, can make a proper bonded repair harder to achieve when a professional does eventually look at it.
If water is actively getting in, place a container inside to collect it, note roughly where the internal wet patch is, and describe that location to the roofer when you call. The internal patch rarely sits directly below the entry point on a flat roof - water travels along the deck before dropping through - but it helps narrow down where to look.
A well-installed EPDM membrane, properly maintained, can realistically be expected to last 30 years or more. Quality torched-on mineral felt, kept clear of debris and checked regularly, typically gives 15 to 25 years of service. The single biggest factor shortening those lifespans - beyond poor installation - is ignored maintenance. A blocked outlet or a flashing that has been lifting for two winters causes far more damage than the repair would have cost.
We cover Lakenheath and the surrounding area. Whether you need a new EPDM roof on a garage, a felt replacement on an extension, or an honest assessment of whether a repair or replacement makes more sense, call Mildenhall Roofers for a written quote and straightforward advice.
No obligation · We usually respond within 2 hours
Storm damage, active leak, damaged ridge - we aim to be on-site within 24 hours.
