Sika Sarnafil

The ONLY domestic approved installer of Sarnafil single ply membrane within the Southampton area.

The only approved installer of Sika Sarnafil in Southampton. Click here to read more about this incredible product.

Single ply membranes have been used for many years  on commercial projects but their high performance means they have become increasingly popular for domestic roofs. The Sarnafil membrane is particularly capturing the imagination of homeowners looking for a good looking, high performance, alternative to traditional flat roofing materials.

Sarnafil roofing membranes are very versatile and ideal for almost any kind of roofing project. The membranes are manufactured in Switzerland to ISO 14001 and have a managed impact on the environment. Sika Sarnafil operate a stringent quality control programmes to ISO 9001.

Life expectancy

The Sarnafil single ply membranes, fitted by Roof Assured by Sarnafil approved installers, have been independently assessed by the British Board of Agrement (BBA) to have a life expectancy* in excess of 40 years (*in their opinion)


The Sarnafil single ply membrane can cope with standing /ponding water without detriment to the product or, with the guarantees.

Wind uplift

The membrane is secured and adhered to the roof structure so offers maximum protection from wind uplift. Sarnafil takes full responsibility for wind calculations on projects over 100m2


The Sarnafil membrane is thermally and dimensionally stable.  Its performance is unaffected by expansion and contraction, but also protects against damaging solar rays. The Sarnafil membrane is also vapour permeable to prevent blisters.


Sarnafil membranes have a unique lacquered top coating providing better resistance to industrial/biological waste and air pollution.

Resistant to root growth

Membranes are resistant to root growth, making them suitable for use under green roofs.

Fire retardant

The membranes are treated with a fire retardant and are self extinguishing and can be used to gain relevant Building Regulations approval.


All laps, joints and details are permanently welded for maximum strength.  Steel reinforced details and a unique seal cope with building movement and guarantees a waterproof wall joint, that will not crack or fail like traditional mortar, lead or sealant. Sarnametal (PVC coated) steel reinforced edge trims are mechanically fixed to form a solid, storm resistant roof edge.  The Sarnafil membrane is fusion welded to the Sarnametal trim to permanently seal the roof edge.


The Sarnafil membranes are virtually maintenance free and carry an insurance backed guarantee from the manufacturer that should any product supplied by them fail, will not just be replaced, but will also cover the installation cost of those replacements.

Installation times

With the new Sarnafil self adhered membrane, installation times on large projects can be reduced considerably.

Flame Free

Sarnafil membranes are cold applied and free from naked flames. They are also homogenous which, when hot air welded form joints which are stronger than the membrane itself.


The membranes have a low environmental impact and when used in conjunction with a high performance thermal insulant can improve household energy performance. The Sarnafil membranes have been used to obtain Ecopoint profiles and ratings for membrane roofs, which can be used to gain credits towards a building environmental rating.

We are part of the global Sika group of companies and a member of The Green Building Council.