Roofing felt is the waterproof membrane that lies directly on the rafters beneath the tiles or slates. Its job is to catch any water that gets past the outer covering — driven rain, ice build-up, or tile gaps — and direct it into the gutters rather than into the roof space. Timber battens are the horizontal strips nailed over the felt, onto which each course of tiles is hooked. Between them, felt and batten form the structural and waterproofing foundation of every pitched roof.
Older roofs commonly used traditional non-breathable felt (often referred to as torched felt), which has a lifespan of 15 to 25 years before it becomes brittle, splits, and stops doing its job. Modern replacements use breathable underlays — they allow moisture vapour out of the roof space rather than trapping it, which significantly reduces condensation and extends the life of the roof structure. When replacing felt and batten, we always use breathable membrane as the upgrade.
The most direct way to check is to go into the loft space and look at the underside of the roof. Old felt that has failed will often be visibly sagging between the rafters, cracked, or show daylight around nail holes and splits. Water staining or damp patches on the felt or rafters after rain are a clear sign the membrane is no longer performing. Condensation dripping from the felt in cold weather, causing damp insulation or wet ceilings below, is another indicator that the felt has become non-functional.
From the outside, tiles slipping more frequently than usual can point to batten decay — when the timber degrades, tiles lose their fixing and shift down the roof over time. A roof of 30 years or more with no history of felt replacement is worth inspecting, particularly if you're already planning tiling or repair work. Replacing felt and batten while the tiles are off is always more cost-effective than coming back to do it separately later.
A full felt and batten replacement on a typical three-bedroom semi-detached, including stripping the tiles, laying new breathable membrane and treated batten, re-laying the tiles, and replacing the scaffolding, typically costs between £5,500 and £7,500. The main variables are roof size, pitch, whether any timber repairs are needed to the rafters, and the tile condition — if existing tiles can be re-used, costs stay lower than if new tiles are also needed.
Partial felt repairs, where a section of the roof is accessible and the damage is localised, can be carried out from £200 upwards depending on the area involved. A free site visit will give you a precise figure. We provide written estimates before any work starts and won't begin without your sign-off.
Felt & Batten Replacement Across Tadley, Reading & Beyond
We carry out felt and batten replacement throughout a 30-mile radius of Tadley, covering Reading, Basingstoke, Newbury, Andover, Bramley, Thatcham, Fleet, Camberley, and Farnborough. Not sure if we cover your postcode? Give us a call.
The answer depends on the type of felt. Traditional non-breathable felt commonly used up to the 1990s typically lasts 15 to 25 years before becoming brittle and ineffective. Modern breathable underlays have longer expected lifespans, often 40 years or more, though the actual performance depends on installation quality and the conditions in the roof space. A roof where condensation has been a persistent problem, or where the roof space runs very hot in summer and cold in winter, will see felt deteriorate faster.
There's no fixed replacement schedule — the right time is when the felt is no longer doing its job effectively. If you're planning a re-tile or full re-roofing project, it always makes sense to inspect the felt condition at the same time. Replacing it proactively while everything is off the roof costs a fraction of what it would cost to strip and re-tile again in a few years.
Scaffolding is erected first to provide safe access across the whole roof. Tiles are then carefully removed, course by course, and set aside where they're in condition to be re-used. The old felt is stripped back, and all the rafters and ridge board are inspected carefully for any rot, split timber, or nail rust. Any damaged structural timber is replaced or treated at this stage before the new system goes down.
New breathable roofing membrane is laid over the rafters, lapped at all joints, and secured before treated timber battens are nailed across. Tiles are then re-laid from the eaves upward, ridge and hip details finished, and any lead work or valley repairs carried out while everything is accessible. The site is cleared and scaffolding removed once the job is checked over. For the tiling element of this process, see roof tiling and slating. For full re-roofing, see new roof installation.
If your roof is showing signs of felt failure, or you're planning re-tiling work and want to check the condition underneath, get in touch. We cover Tadley, Reading, Basingstoke and a 30-mile radius. Free estimates, all work guaranteed.
This is what we do best.
Discover what our customers have to say about us.