Pro Clima Solitex Plus (1.5m standard roll) 1.5m x 50m

Pro Clima Solitex Plus is a highly vapour-permeable, windtight roofing underlay suitable for use directly over rafters or on top of insulation. Offering excellent resistance to wind-driven rain and UV exposure, it is supplied as a 1.5m x 50m standard roll covering 75m².

What Sets Solitex Plus Apart from Standard Breather Membranes

Most breather membranes on the market use a microporous film — a layer riddled with tiny holes that allows moisture vapour to pass through while (in theory) keeping liquid water out. The problem is that microporous membranes are vulnerable to contamination. Resins, preservatives, and oils from the timber they're in contact with — as well as common on-site chemicals — can reduce the surface tension of water enough to cause rain to seep through. On a long build programme, that's a real risk.

Solitex Plus uses a different approach entirely. Its central functional layer is a monolithic TEEE membrane — a closed-cell film with no holes at all. Moisture vapour passes through by diffusion rather than through openings, which means there's nothing for preservatives or chemicals to exploit. The result is a membrane that stays fully watertight in all conditions, regardless of what the timber below it has been treated with.

Four-Ply Construction for Site Conditions

Solitex Plus has four distinct layers: a polypropylene fleece backing, a high-strength reinforcing mesh, the central monolithic TEEE membrane, and a blue polypropylene felt top surface. This construction gives the membrane exceptional physical toughness — nail tear resistance exceeding 350N, high tensile strength, and the ability to handle foot traffic during installation without damage. It's a membrane that can be rolled out, fixed, walked over, and left exposed while the rest of the build catches up around it.

Where It's Used

Solitex Plus is an external membrane — it sits on the outside of the insulation, forming a windtight, weatherproof, and breathable barrier. Typical applications include:

• Pitched roofs at 15° or more — used as a roof tile underlay or sarking membrane beneath tiles and slates
• Timber frame walls — as an external breather membrane behind cladding (closed or open jointed)
• Suspended timber floors — fixed to the underside of joists to prevent draughts while allowing moisture to escape
• New build and retrofit projects using blown-in or dense-pack insulation, where high nail tear resistance is essential

Three Months' UV Exposure

Like the DA membrane internally, Solitex Plus is engineered to cope with being left exposed during construction. It can handle up to three months of UV and weather exposure before tiles, cladding, or other protection is installed over it — a practical reality on most building programmes, and something cheaper membranes aren't reliably rated for.

Note on Roof Pitch

Solitex Plus is specified for pitches of 15° or above. For lower pitches (under 10°), consider Solitex Weldano. If you're unsure which membrane is right for your project, get in touch.

Technical Specification

• Roll size: 1.5m x 50m (75m² coverage)
• Roll weight: 13kg
• Construction: 4-ply — PP fleece / reinforcing mesh / monolithic TEEE membrane / PP felt
• Sd value: 0.05–0.3m (diffusion open)
• G value (vapour resistance): 0.20 ±0.05 MNs/g
• Water tightness: >2,500mm (W1 — highest classification)
• Nail tear resistance: >350N
• Elongation: 15% ±5% (MD and CD)
• Temperature range: -40°C to +100°C
• UV exposure: up to 3 months
• Fire rating: Class E
• Chemical resistance: fully resistant to timber preservatives, wood resins, and site chemicals

Certifications

• BBA Certificate 14/5155
• CE marked
• Passive House Institute certified component (phA)
• NHBC accepted
• EN 13984 compliant

Warranty

10-year warranty when installed correctly as part of the complete Proclima system with approved insulation materials. 6-year warranty when used in combination with non-Proclima products.