Installation Details

Installation Recommendations

ProctorWrap Air Tight (AT) should be installed in accordance with AS/NZS 4200.2 Pliable Building Membranes and Underlays, Part 2 Installation Requirements. ProctorWrap AT should be installed with the printed face outwards.

The membrane must be secured at regular intervals not exceeding 300mm to prevent damage by wind. Fix ProctorWrap AT to all framing members after being pulled taut over the frame.

Apply to run horizontally to the outer face of external stud walls, from the bottom plate up, over the flashing. It is essential that the lowest timbers or steel frame sections are protected from moisture. Upper layers should overlap lower layers to shed water away from the membrane. Vertical laps should be staggered wherever possible and should overlap by one full stud spacing. The edge distance to fixings should be a least 50mm.

All laps should not be less than 150mm unless taped.

When fixing to timber frames, metallic-coated clouts, 20mm long 6-8mm staples, or punched multi-point metallic-coated steel brads should be used.

When fixing to steel or aluminium, use tek screws with either 20mm diameter washers or through hardboard strips.

When fixing to plywood or other timber substrates use metallic-coated clouts, 20mm long 6-8mm staples or punched multi-point metallic coated steel brads. When the membrane is applied to a substrate ensure that the positions of the studs are marked to identify where further fixings such as wall ties can be used.

Stainless steel fixings are recommended as “good practice” and are required in corrosive environments.

At penetrations, such as vent pipes, an additional piece of ProctorWrap AT should be fixed around the penetration and taped into position, to channel water away from the opening.

If the membrane is used to provide a continuous air tight layer, all overlaps in the membrane should be sealed with Proctor Probond Flex pressure sensitive adhesive tape.

Durability

Although ProctorWrap AT can be used as temporary protection during construction, it can not be used as a primary waterproofing membrane. The product may be damaged by careless handling, high winds or vandalism, and should not be left uncovered for longer than is absolutely necessary. Any damaged areas should be replaced before completion.

Ensure that ProctorWrap AT is covered up by the primary cladding or roofing material as soon as possible, and not left exposed to UV for longer than 2 months. ProctorWrap AT is not to be used in open joint rain screen cladding installations where it could be exposed to long term UV radiation. For advice on such applications please contact Proctor Group Australia.

Some timber treatments may impact on the water resistance of the product so the membrane should only be applied once such treated timber has dried.

Delivery, Storage and Site Handling Requirements

 Rolls of ProctorWrap AT are delivered to site, individually wrapped in a transparent polyethylene sleeve. A ProctorWrap AT ‘User Guide’ is included with each roll. Rolls may be stored flat or upright on a clean, level surface and kept under cover.

At penetrations, such as vent pipes and rooflights, an additional piece of ProctorWrap AT should be laid upslope and taped in position, to channel water away to each side of the opening.

Attention to detail is important. Avoid blockages where possible that would otherwise prevent the free drainage of water. With secret fix and standing seam roof installations a drainage mat or packing must be used to create a clear drainage path. At the eaves ensure that the ProctorWrap AT is dressed into the gutter. Anti-ponding boards should be installed to support ProctorWrap AT at the eaves of roof pitches below 20° to ensure that any water collected by the membrane will be
discharged into the eaves gutter.

Windows

Run ProctorWrap AT over openings and leave covered until fenestrations are to be installed.

Cut the membrane on a 45° diagonal from each corner of the opening, fold the flaps inside and fix to the inside frame of the opening.

A complete water tight seal is achieved at penetrations by installation of ProctorWrap Corners or Hyperflash flexible butyl tape. Please consult the separate installation guide for details of recommended installation around windows. Advice on accessories and suitable tape specifications for specific applications is available from Proctor Group Australia.

Condensation Risk

There are a large number of factors that need to be considered in assessing and managing condensation risk. Such factors include the local climate, building use, position, thickness and type of bulk insulation, position and integrity of vapour barriers, and the degree and location of mechanical or passive ventilation both in the roof space and the interior. It is highly recommended that designers run a condensation risk analysis.

In colder climates or buildings with a high internal vapour pressure, the high vapour permeability of the Proctor Roofshield or ProctorWrap High Perm (HP) membranes may be required.

For further information on the risks of condensation please refer to the Building Technology File 3 entitled “Condensation’ published by CSIRO in June 2001.

Please contact us for a full copy of the installation guide or to discuss specific constructions. Advice including R-Value calculations and condensation risk analysis is available from Proctor Group Australia.

Installation of ProctorWrap AT

Key points to watch:

1. It is "good practice" for the membrane to be separated from the exterior cladding by a minimum 20mm vented cavity. This allows for the drainage of any moisture that has penetrated the exterior cladding or condensation that may form on the rear face of the cladding.
2. Adequate provision for the drainage, absorption or diffusion of moisture is required to ensure that moisture is not left trapped between the ProctorWrap AT and the external cladding. This is especially important for vapour tight cladding's such as steel.
3. Care should be taken when installing bulk fibre insulation so that this does not restrict drainage within the cavity.
4. Upper layers should overlap lowers layers to shed water away from the membrane.
5. Vertical laps should be staggered wherever possible and should overlap by one full stud spacing.
6. Follow installation manuals from cladding manufacturers and consult the supplier where advice is contradictory.

Built up metal roof / metal side cladding 

Typical Section Detail

Key points to watch:

1. Ensure the vapour control layer is continuous and all laps and penetrations are sealed effectively.

2. On a low pitch metal roof, the draping of ProctorWrap AT between purlins can result in ponding which is unsatisfactory and should be avoided.

Ridge Detail

Key point to watch:
The lap between the vapour control layers should be sealed with two continuous runs of 15mm wide Probond Tape.

Eves Gutter Detail

Key points to watch:
1. The vapour control layer in the wall needs to be effectively sealed to the vapour control layer in the roof.

2. Ensure that the ProctorWrap AT breathable membrane drains freely into the gutter.

Verge Detail

Key points to watch:
1. Ensure the vapour control layer is fully sealed to the top hat with Probond Flex Tape. Also ensure the top hat is sealed to the pipe using a suitable sealant.

2. Ensure that ProctorWrap AT is turned up around the pipe to prevent condensate draining into the roof void.

Pipe Penetration

Key points to watch:
1. Ensure the vapour control layer is fully sealed to the top hat with Probond Flex Tape. Also ensure the top hat is sealed to the pipe using a suitable sealant.

2. Ensure that ProctorWrap AT is turned up around the pipe to prevent condensate draining into the roof void.