Question answered
Rotten felt at the eaves: what is an eaves support tray?
The short answer
An eaves support tray is a strip of rigid plastic fixed across the rafters at the bottom of the roof. It props the underlay up and guides water into the gutter. Rotten felt at the eaves is usually underlay that has sagged below the fascia line and held water for years. The fix is normally to lift the lowest few courses of tiles, cut out the perished felt and fit trays, with no need to strip the whole roof.
Underlay tends to perish first at the eaves, where it sags towards the gutter and stays wet. An eaves support tray cures that detail, and it can usually be fitted without stripping the roof.
Why felt rots at the gutter line
At the eaves the underlay has a hard job. It has to run past the fascia and into the gutter so that any water on top of it drains out and does not run back into the roof. Over the years the felt sags in the gap between the rafters, where nothing is holding it up. Sagging felt forms a shallow pouch, and a pouch holds water.
That water sits against the felt through every winter. Bitumen felt softens and starts to flake, battens beneath stay damp, and the lowest courses of tiles end up resting on a wet, weak base. Gutters that overflow, wind that lifts the loose edge and the damp that rises from the gutter itself all add to the damage. From the garden it shows as a dark, ragged edge of felt drooping into the gutter. From the loft it shows as a stained rafter end or a damp timber where the rafters rest on the wall.
What an eaves support tray actually does
The tray is a rigid strip, usually plastic, that sits on top of the fascia and under the first course of tiles. The underlay is laid over it, so the felt is held in a straight, falling line from the roof slope into the gutter, with no pouch. Water that gets under the tiles runs down the underlay, over the tray's lip and into the gutter.
The detail also matters for air. Where a high-resistance underlay is used, Marley's cold-roof advice is a 10 mm gap running the length of the eaves above 15° pitch and 25 mm at 15° or below, so a tray that closes that opening causes trouble of its own. Trays that leave a vent opening, or work alongside a separate eaves vent, avoid this. The right product depends on the roof, which is something we choose on the day, from what we find on your fascia and rafters.
How it is fixed without stripping the roof
This is a repair done from the bottom up. The eaves course and the next few courses of tiles are lifted and stacked, and the batten ends are checked. The perished felt is cut away back to sound underlay, and any rotten timber is dealt with. The trays are fixed to the rafters, a new strip of underlay is lapped over them and under the existing sheet higher up, and the tiles go back.
Because the work stays near the edge, the rest of the roof is untouched, and the job is usually far smaller than a re-cover. Damaged or broken tiles are swapped as they come up. The eaves are also where tiles take the most wind, so we check that the lowest courses are held to the standard BS 5534 asks, which our note on tile fixing in coastal wind explains.
What we find once the eaves are opened
Lifting the edge shows what has been going on. Battens at the lowest course are often the first to rot, and rotten roof battens sets out how they are replaced. Rafter ends that have sat wet can be soft and need sistering, and fascias and soffits behind them may need attention too.
Gutters come into it as well. A gutter that does not fall towards its outlet will hold water against the felt, and one with supports too far apart sags. Brett Martin spaces gutter supports 900 mm apart at most, and the fall that manufacturers usually recommend runs from about 1:600 to 1:350 to the outlet, depending on the system. Each of these gets a photograph as the work opens up, so you can see the cause for yourself, and the written quote comes afterwards. A slipped or rotten fascia bracket line is as much a part of the diagnosis as the felt itself.
Eaves patch or wider underlay renewal
A tray repair suits a roof whose underlay is sound higher up and has failed only along the bottom edge. This is the most common pattern we expect, and it is the smaller job to put right. The check is in the loft. If the felt above the eaves is intact, flexible and dry, and there is no daylight or tide mark further up, the local job holds. If it has become brittle across the slope, tears when touched or has gone through at the laps, patching the edge only moves the failure to the next lap.
That wider situation is dealt with in torn roof felt. Which job is right is something we only recommend after we have seen the roof, and we choose the smaller one whenever it will properly solve the fault. The rest of the pitched roofing work we do is on the pitched roofing hub.
Eaves repairs in practice
Does an eaves repair need scaffold?
On a bungalow it often does not, because a ladder and a working platform can reach the edge. On a two-storey house scaffold is normally the safe way to work at that height. The survey decides, and whichever quote you accept, check that it covers scaffolding and VAT.
Can the gutter be put right at the same time?
Yes, and it makes sense to. The gutter often has to come off or be lowered to reach the eaves, so its fall and brackets can be corrected while it is down. Doing it once is better than disturbing the same edge twice.
Tell us about your roof
Describe what is happening and we will call you back to arrange a visit.
- Photographs of what we find
- A written quote with one total price
- Or call 01903 299063
10-year workmanship guarantee, in writing.