Tyvek | Dupont Tyvek

Tyvek, a renowned brand under DuPont, is synonymous with delivering superior and durable building envelope solutions. In this category on Insulation4less, explore an array of Tyvek products each crafted with precision and commitment to safeguard your structures, ensuring they stand resilient against the elements. Understanding each product’s unique offerings and suitable application will guide you towards constructing a dependable building envelope.

Which Tyvek Product Do I Need?

Choose by position in the build-up first, not by brand name alone. A breather membrane belongs towards the external, colder side of a wall or pitched roof and is designed to let water vapour escape while resisting external water. An air and vapour control layer (AVCL) belongs towards the internal, warmer side and restricts vapour movement and air leakage. Using an internal vapour barrier where a vapour-open external membrane is required can change the moisture behaviour of the construction.

Tyvek Housewrap vs Supro vs AirGuard

Housewrap and Supro are both vapour-open, but they are not interchangeable for every detail. Housewrap is the lighter wall product. DuPont specifies it for timber frame, steel frame and concrete or masonry wall construction, fixed directly to sheathing, insulation or blockwork. Supro is reinforced for the mechanical demands of pitched roofs and can be installed supported or unsupported. Supro Plus adds an integral adhesive strip, useful where sealed laps are required for wind resistance or airtightness.

AirGuard products work on the other side of the construction. AirGuard Control is an internal AVCL with an Sd value of 5 m. AirGuard Reflective is a much stronger vapour barrier at Sd 2,000 m and has a low-emissivity face. DuPont states that its reflective thermal benefit is achieved when used with an air gap. Do not select AirGuard Reflective simply because the foil face looks more substantial; the condensation design of the complete build-up matters.

Is Tyvek Waterproof or Breathable?

Tyvek breather membranes are designed to resist liquid water while allowing water vapour to pass through. DuPont classifies Tyvek Supro as a Class W1 vapour-permeable roof underlay with a nominal Sd value of 0.025 m. This means water resistance and breathability are not contradictory: one describes resistance to liquid water, while the other describes the movement of water vapour through the membrane.

A Tyvek breather membrane is not a substitute for a finished roof covering, tanking system or damp-proof membrane. It must be installed for its specified application, with the correct laps, fixings, penetrations, eaves details and associated sealing products.

Roof Installation: Supro and Supro Plus

Tyvek Supro is a reinforced Type LR vapour-permeable underlay designed for pitched roofs. It can be installed in supported or unsupported applications. For Tyvek Supro Plus, DuPont specifies 150 mm horizontal laps. Vertical laps must be at least 300 mm and positioned over rafters.

Fixings should be installed at maximum 300 mm centres to each rafter or counter batten, with rafters spaced at no more than 600 mm centres. For unsupported installation, DuPont specifies a nominal 10 mm drape. These requirements are specific to Tyvek Supro Plus and should not be treated as universal installation figures for other breather membranes.

Tyvek Supro Plus at the Eaves

At the eaves, DuPont specifies an appropriate UV-resistant eaves sheet laid over the fascia board or rafter ends and extended into the gutter. Tyvek Supro Plus is laid parallel to the eaves, overlapping the eaves sheet and extending to the outside edge of the fascia board or rafter ends.

DuPont specifies bonding the membrane to the eaves sheet with Tyvek Double-sided Tape to create a weather-tight seal. This arrangement protects the roofing underlay from prolonged UV exposure at the eaves and provides a route for water towards the gutter.

Does Tyvek Supro Need Counter Battens?

For a fully supported installation where the breather membrane is laid directly over insulation, DuPont specifies the use of counter battens. The counter battens lift the tiling battens clear of the membrane and help provide an effective drainage path towards the eaves.

The complete roof must also be designed and installed for the particular building, exposure and wind conditions. Where applicable, installation should comply with the current version of BS 5534 and the relevant DuPont installation instructions. For wind-uplift requirements, DuPont specifically directs installers to the current version of BS 5534 Annex A.

Tapes and Adhesive Solutions

Ensuring that your insulation and housewrap solutions adhere securely and form a tight seal is vital. The Tyvek Single and Double-Sided Tapes, like the Tyvek 2060B Single Sided Acrylic Tape and Tyvek Double Sided Butyl Tape, provide robust adhesion, ensuring that your building envelope remains secure and impermeable to unwanted air and moisture. Tyvek Flexwrap Tape is a versatile adhesive solution, flexible and dependable for ensuring continuity at building envelope penetrations.

Vapour Barriers and Control Layers Product

Manage moisture effectively with Tyvek Airguard Reflective Vapour Barrier and Tyvek AirGuard Control. These products not only restrict the passage of external moisture into the building but also reflect heat, thereby contributing to energy efficiency. Tyvek’s vapour control layers are pivotal in maintaining a controlled environment within the building, ensuring that the insulation remains dry and effective.

Roofing Underlays

Navigate through a range of roofing underlays like Dupont Tyvek Supro, Tyvek Supro Plus, and Dupont Tyvek UV Facade which are meticulously designed to offer secondary protection against external elements like rain, wind, and snow. While the UV Facade also provides prolonged UV resistance, ensuring durability and longevity even in prolonged exposure to sunlight.

Dupont Tyvek 

DuPont Tyvek is a high-quality, durable material that offers superior protection against moisture and air infiltration for building envelopes. This innovative product is designed to provide long-lasting performance and energy efficiency for residential and commercial construction projects.

Frequently Asked Questions

What is the purpose of Tyvek?

Tyvek building membranes help manage water, air and water vapour through the building envelope. Exterior breather membranes resist external moisture while allowing vapour to escape. Internal AirGuard layers control air leakage and vapour from the warm side. The correct product depends on whether the detail is a roof, wall, façade or internal AVCL.

Is Tyvek a vapour barrier?

Standard Tyvek Housewrap and Supro are breather membranes, not high-resistance vapour barriers. Their nominal Sd values are 0.01 m and 0.025 m respectively. AirGuard products are installed internally for vapour control: AirGuard Control has Sd 5 m, while AirGuard Reflective has Sd 2,000 m according to DuPont.

What is the difference between Tyvek Housewrap and Tyvek Supro?

Housewrap is a lightweight external wall membrane at 63 g/m², intended for timber frame, steel frame and masonry wall systems. Supro is a reinforced 145 g/m² membrane designed for supported or unsupported pitched roofs and can also suit selected wall and floor applications. Supro Plus adds integral adhesive lap tape.

What is the difference between Supro and Supro Plus?

Supro and Supro Plus use the same 145 g/m² membrane with nominal Sd 0.025 m and W1 water tightness. Supro Plus includes an integral adhesive strip for sealing horizontal laps. DuPont positions that feature for improved wind resistance and airtightness where the roof design calls for sealed laps.

Can Tyvek be laid directly on insulation?

DuPont states that its breather roof membranes can be laid directly over insulation in a fully supported arrangement, with counter battens installed above. Housewrap can also be fixed directly to insulation in suitable wall systems. The complete build-up, condensation risk and fixing method still need to follow the relevant DuPont installation guidance.

How much should Tyvek Supro overlap?

DuPont's Supro Plus pitched-roof installation guidance specifies a 150 mm horizontal lap. Vertical laps should be at least 300 mm and positioned over rafters. Supro Plus incorporates adhesive lap tape for sealing horizontal laps. These dimensions are product-specific installation requirements and should not automatically be applied to other breather membranes.

Which Tyvek should I use for a pitched roof?

Tyvek Supro is the reinforced vapour-permeable Type LR underlay in this range for supported and unsupported pitched roofs. Choose Supro Plus where integral adhesive lap tape is useful for sealed laps, wind resistance or airtightness. The roof pitch, support condition, wind zone and project specification should be checked before ordering.

Which Tyvek should I use for timber-frame walls?

Tyvek Housewrap is DuPont’s standard breathable wall membrane for timber-frame construction and is also suitable for steel-frame and masonry wall systems. FireCurb is the alternative where the specified wall build-up calls for its flame-retardant performance. UV Facade is intended for open-jointed rainscreen cladding exposed to higher UV levels.

Is Tyvek insulation?

Tyvek building membranes are not thermal insulation boards, slabs or rolls. They manage weather, air and moisture around insulation and the structure. A correctly detailed membrane can help insulation remain dry and reduce uncontrolled air movement, but thermal resistance and U-value calculations come from the complete construction and its insulation layers.

Do Tyvek joints have to be taped?

DuPont says taping wall breather-membrane joints is generally optional, although sealed joints can improve airtightness and windtightness. Some roof designs and airtightness strategies specifically benefit from sealed laps. Supro Plus includes integral lap tape, while 2060B Acrylic, Butyl and FlexWrap tapes are intended for different sealing details.