Maintaining My Home

• reinstall the gutter (or install a replacement gutter) to provide an even fall to the outlet(s)

• there is no minimum fall given for external gutters generally in the Building Code. Guttering manufacturers in New Zealand recommend minimum falls for their products, from 0.5 mm per metre of length to 2 mm per metre (the 2 mm is for metal gutters)

• clear the debris out and then begin a regular maintenance programme as often as necessary to keep it clear – annually, six-monthly or quarterly

• if outlet is frequently blocked with leaves or twigs, trim back the trees or install leaf guards over the gutters

• clear the debris out, taking care not to push it into the downpipe. Begin a regular maintenance programme as often as necessary to keep it clear – annually, six-monthly or quarterly

• if outlet is frequently blocked with leaves or twigs, trim back the trees or install leaf guards over the gutters

• remove any obvious blocking materials (such as tennis balls, leaves/twigs or plastic bags). Always pull the blockage out – avoid pushing it further into the downpipe

• begin a regular maintenance programme as often as necessary to keep the downpipe and gutters clear – annually, six-monthly or quarterly

• if the system is frequently blocked with plant matter, cut back overhanging vegetation and/or install leaf guards over the gutters

• check that there is a sufficient number of brackets holding the guttering to the fascia, that they are close enough together and are not broken. Brackets should be no greater than 500 mm apart (300 mm in areas of high wind or in alpine areas where snowfall is possible). Fix with stainless steel fixings at least 20 mm long. Ensure the gutter complies with manufacturer recommendations, having a minimum fall of at least 0.5–1 mm per metre of length (or 2 mm with metal gutters)

• check that the fascia is still in good condition – rot in the fascia may result in sagging guttering. Where this is the case, replace the fascia, paint it and then refix the guttering, or install new guttering. Ensure the gutter complies with manufacturer recommendations, having a minimum fall of at least 0.5–1 mm per metre of length (or 2 mm with metal gutters)

• remove a section of the gutter – where guttering has been fixed with solvent cement, this may require cutting out with a fine tooth saw. Install an expansion joint to each end, sliding the guttering in without using solvent cement to allow for movement. For long gutters, insert an expansion joint at the midpoint

• some proprietary gutters have a small lip at the outlet leaving some water remaining after rainfall, but this should evaporate 

• where the guttering is in a sound condition, with an appropriate fall to the outlets, allow the ice or snow to melt and then check the gutter for damage. Brackets fixing the gutter to the fascia should be closer – no more than 300 mm apart – in areas where snowfall is likely 

if the downpipe is too small for area of roof draining to it, install a larger diameter pipe. Ready-made proprietary outlets and downpipes are available. Build magazine has published an article about how to calculate the right size for a downpipe here