Some handy hints to spotting risks in cladding and leaky buildings These hints are common to stucco, EIFS and texture coated fibre cement. Intersect

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Some handy hints to spotting risks in cladding and leaky buildings

These hints are common to stucco, EIFS and texture coated fibre cement.

Intersecting roofs that direct water behind the cladding
Check that the end of the apron flashing is stop-ended, to divert water into the gutter. A sealant joint at this point is not satisfactory.

Poor maintenance of paint coatings
Waterproof coatings must be maintained to a high standard. Recoat in the most exposed areas at least every five years. Many cladding types rely on the paint to protect the cladding material.

Penetration of the cladding by spoutings and fascias
It’s important that the spouting or fascia was not fitted before the cladding. Water could enter behind these weak points. If the spouting disappears into the cladding, it should be removed, the cladding completed and the spouting shortened and refitted.

Claddings penetrated by fixings
Fixings and pergolas that go through the paint and cladding need protection with gaskets. Pipe penetrations need a sleeve and a formed sealant joint.

No step down at doorways/decks
There must be a fall away from the doorway to remove rainwater. Enclosed decks without a roof require a 100mm step at the doorway.

Reliance on sealant
A formed sealant joint made to a prepared gap can provide a good weathertight joint and may continue to work well for 10-15 years. Sealant joints will deteriorate and must be able to be inspected and protected from sunlight. Joints formed by smearing sealant over or into a gap or failed joint will not last well. They are unable to flex and are likely to separate from what they are attached to.

Insufficient clearance
Cladding needs to be 100mm above a paved surface and 175mm above grass, garden or other non-paved surfaces. Decks, flat roofs or any other sloping roofs, require 35mm clearance from the bottom of the cladding.

Parapets without cappings
No stucco cladding should have a parapet where the plaster is carried over the top. The plaster will crack at corners and junctions. The only solution to this problem is to provide a metal cap flashing, correctly installed and jointed.

Recessed windows allowing water to penetrate flat sills
Stucco used on a flat or near flat surface (as in B in the diagram) is not waterproof. Cladding is prone to cracking at the corners and this detail is no longer allowed under the Acceptable Solution E2/AS1.

Flashings missing from windows and doors
The minimum requirement is a head flashing that extends up behind the cladding and slopes out over the aluminium window or door facing, extending past the end of the window/door by 20mm and lapping the aluminium by 10mm.

Junctions that crack
Cracking may occur at places where there is a sudden change of direction.

Horizontal surfaces and handrails
The top of all handrails or parapets should be constructed with a slope of at least 15 degrees. This will drain water off the surface quickly, preventing water lying on the surface and increasing the risk of water entry.

No drip edge
Horizontal surfaces of cladding that form the soffit above windows, at the bottom of walls or over flashings should not be formed flat. Water can track and be blown across these surfaces. A groove (6mm wide and deep) set back from the edge or a sloping underside forming a sharp edge at the front surface will cause any water to drip off.

Sheets not installed correctly
Fibre-cement sheets should not have joints above the edge of an opening, and be continuous around the corner of the opening with the joint 150-200mm in from the corner. Cracking is the best evidence of this.

Note: If you think you have a leaky home, you should seek professional advice before making any repairs.

To find out whether the house you are buying or selling is at risk of leaking, call HomeBuyers Reports. Our inspectors have over 500 building inspections of risk buildings under their belts so we can give you unbiased advice.

0800 HMBUYRS (0800 462 897), www.homebuyersreports.co.nz

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