There is one way to make a squirrel problem into a more expensive problem, and it is to close the roof up properly in the wrong sense.
A roof space has to breathe, and understanding why is what separates proofing from blocking.
Why a loft needs to ventilate
A house produces a great deal of water vapour — cooking, washing, drying, breathing. Some of it passes up through the ceiling into the roof space, where the air is colder. Cold air holds less moisture, so it condenses on the coldest surfaces it meets: the underside of the roof covering, nails, and the timbers.
Ventilation removes that moisture-laden air and replaces it with outside air, continuously. It is not a nicety; it is what keeps the roof structure dry.
What happens when it stops
- Condensation on the underside of the roof, dripping onto the insulation below
- Wet insulation, which stops insulating and does not dry out
- Damp timber, and in time decay
- Mould, on timbers, on stored belongings and on the underlay
- Staining on ceilings, which looks exactly like a roof leak and sends everybody looking in the wrong place
The cruel part is the timing. The squirrel problem stops immediately and the condensation problem appears over the following winter, by which point nobody connects the two. It is discovered as a roof leak that no roofer can find.
Where the ventilation comes from
Overwhelmingly at the eaves — a continuous gap along the roof edge, which on modern housing is provided deliberately by over-fascia vents or soffit vents. Some roofs add high-level ventilation at the ridge or through tile vents. Kesgrave's largely modern housing generally has purpose-made provision, which makes it easy to see and easy to wreck.
The awkward fact is that the eaves is also the commonest entry point, so the opening that has to be closed and the opening that has to stay open are frequently the same detail.
How proofing handles it
- Mesh, not solid material. Steel mesh of a small aperture closes the detail to animals while air passes freely
- Purpose-made metal closures at the eaves, designed to keep the ventilation path
- Existing vents replaced rather than covered where a grille has been damaged
- Alternative provision where a detail genuinely has to be closed solid — usually tile or ridge vents
What not to use, for this reason as well as the others
Expanding foam, mastic, timber and plastic sheet all block the airflow completely as well as being gnawed through. So the improvised repair fails twice: it does not keep the animal out, and in the weeks before it fails it is doing quiet damage to the roof structure.
If a loft already shows signs
Damp timbers, mould on the underlay, wet insulation or a musty smell where there was none. Worth looking at whether ventilation has been blocked at some point — by a previous repair, by insulation pushed hard into the eaves, or by boarding. Eaves vent trays exist precisely to stop insulation choking the airflow, and they are frequently missing.
Questions
Does mesh really let enough air through?
Yes — the right aperture closes the detail to animals while the airflow continues. That is why it is used rather than anything solid.
My insulation goes right into the eaves. Is that a problem?
It can choke the ventilation path. Eaves vent trays keep a gap, and they are often missing.
Could my ceiling stain be condensation rather than a leak?
It happens, and it is commonly mistaken for a leak. Blocked ventilation is the usual cause.
Squirrel Control Kesgrave
Squirrel control in Kesgrave is £280 fixed cost. Proofing work, where it is needed afterwards, is £180. Call 01502 630 122 and tell us what you have heard or seen.
For squirrel control in Kesgrave, call 01502 630 122, or read the Kesgrave squirrel control page.