How to cure or prevent roof condensation.

universal roofspace ventilation

Use regulation compliant roof vents installed easily from inside.

Without positive ventilation, roofs blanketed in underfelt are bound to suffer the effects of condensation. An issue compounded by increased insulation.

Some, wrongly, believe that to ventilate a tiled roof they must make holes in it, breach the protective underlay and then fit intrusive external devices.

There's a better way

An important feature of a roof is its ability to breathe easily through its own surface. ie through the gaps in the roof tiles.

Air moves freely in the batten cavity between the tiles and the roofing membrane.

lapVents fit into the roof membrane overlaps in opposing pairs to allow free moving air to flow across the loft space to keep the loft dry and condensation free.




Originally devised for the conservation industry, listed buildings in particular, lapVent's unique features make it suitable for wider applications including new build.

lapVents can be used in any roof with a membrane and small free laid unsealed materials i.e stone, slate & clay/concrete tiles. Totally unexposed and invisible from the outside.

There is no need to identify and match tile types.

Installed from the loft space, fitting can be completed quickly in any weather conditions. No need for costly scaffolding, specialist tools or skills. This results in reduced costs, health & safety risks and downtime. A DIY product.

Be mindful when choosing a roof vent system as many vents on the market do not comply with Building Regulations or British Standards regardless of any purchased certification.

Unprotected gaps made between roofing membrane overlaps, new and old, will endanger the overall stability and weatherproof effectiveness of a roof, which will put a building a risk.

lapVents exceed current UK/Euro Building Regulation specifications and British Standards. The following features of lapVent will show some of what to look for when choosing a roof vent system.

Wind-driven rain or snow is captured by self-draining storm baffles which discharge moisture harmlessly back down the roof.  (BS 5534 : Part 1 ;1997 . Section 3 3.2.2)

To safeguard against wind uplift damage (BS5534), lapVents automatically govern extreme negative and positive wind loads via a closing safely flap.

Three flexible diffuser blades dampen air flow and deflect moisture droplets harmlessly away down to the guttering whilst two retaining walls deflect cross flowing air and maintain a clear reservoir area within the batten cavities.

A mesh filter protects against bird, rodent and large insect infestation.

lapVent is the only roof-space ventilation of its kind to hold the prestigious Millenium Product Award issued by the Design Council.

Environmentally sound. The majority of the lapVent is manufactured from high impact recycled plastics.

Everything you need is included in each kit?

1 x lapVent 1 x membrane repair sheet 2 x pre drilled battens 1 x rafter strap 1 x fixings pack

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