SIGA Majcoat 350 Breathable Membrane for Pitched Roofs - 1.5m x 50m roll

SIGA Majcoat 350 Breathable Membrane for Pitched Roofs - 1.5m x 50m roll
SIGA Majcoat 350 Breathable Membrane for Pitched Roofs - 1.5m x 50m roll
Guide Price
SIGA Majcoat 350 Breathable Membrane for Pitched Roofs - 1.5m x 50m roll
SIGA Majcoat 350 Breathable Membrane for Pitched Roofs - 1.5m x 50m roll
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SIGA Majcoat 350 Breathable Membrane for Pitched Roofs - 1.5m x 50m roll
Guide Price: £462.02 (£554.42 inc VAT)
Price per m2: £6.16/m2 (£7.39 inc VAT)
  • Product Code: A1-7696
  • Delivery Time: 3 - 5 days
  • Brand: SIGA
  • Model: 1.5m x 50m - 75m2
  • Weight: 26.25kg
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SIGA Majcoat 350 Breathable Membrane for Pitched Roofs - 1.5m x 50m roll

Length: 50000mm
Width: 1500mm
Roll Coverage: 75m2
Weight/m2: 0.35kg
Weight: 26.25kg

SIGA Majcoat 350 is a top‑tier, diffusion‑open, nail‑tight pitched‑roof membrane designed for maximum durability, superior weather protection, and long‑term performance in demanding roof assemblies. With a high basis weight of approx. 350 g/m², it is SIGA’s most robust Majcoat variant, ideal for premium roof constructions and harsh site conditions. SIGA Majcoat 350 is a heavy‑duty breathable roof underlay engineered for installation above rafters in pitched roofs. Its sd‑value of approx. 0.15m ensures safe moisture transport out of the roof build‑up, preventing condensation and maintaining the integrity of insulation layers.

The membrane’s exceptional tear resistance, high UV stability, and nail‑tight performance make it suitable for both traditional and modern roof designs, including open‑joint cladding up to 20mm. The increased weight and reinforced structure provide maximum mechanical strength, ideal for challenging installations, high wind loads, and long‑term durability. Majcoat 350 is compatible with all SIGA sealing products, ensuring a fully integrated wind‑tight and watertight roof system. SIGA Majcoat 350 is a premium, heavy‑duty breathable membrane offering maximum durability, exceptional tear resistance, and reliable moisture management for pitched roofs. Its robust construction and wind‑tight performance make it ideal for demanding roof assemblies requiring long‑term protection and stability.

CHARACTERISTICS

  • Premium heavy‑duty membrane - approx. 350 g/m² for maximum robustness.
  • Highly breathable membrane - sd ≈ 0.15m for safe moisture transport.
  • Wind‑tight and weatherproof - protects insulation and structure from wind and rain.
  • Nail‑tight performance - reinforced layers resist puncture from fixings.
  • UV‑stable - suitable for open joints up to 20mm.
  • Robust 3‑layer construction - durable functional film with protective layers.
  • Wide temperature resistance - reliable performance in extreme conditions.
  • Compatible with SIGA tapes - ensures airtight and wind‑tight detailing.

APPLICATION

  • Premium pitched roof underlay for high‑performance buildings
  • Pitched roof underlay for wind‑tightness and weather protection
  • Breathable roof build‑ups
  • Open‑joint cladding up to 20mm
  • Timber‑frame roof construction
  • High‑performance insulation systems
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