Spring Roof Inspection: What to Check After Winter

Winter in New Zealand is tough on roofs. Between heavy rain, strong winds, UV exposure, and — in many regions — frost and coastal salt spray, your roof takes a real battering from May through August. A thorough spring inspection is one of the smartest maintenance habits a homeowner can develop, catching small problems before they become expensive ones.

Why a Spring Roof Inspection Matters

A damaged or deteriorating roof doesn't just let in water — it can compromise your home's insulation, cause mould and rot in the structure, and lead to significant repair bills. BRANZ research consistently shows that early detection of weathertightness issues is far cheaper to fix than deferred maintenance. A spring inspection gives you a clear picture of what winter has done, and enough time to organise repairs before the next wet season arrives.

Prevention is always cheaper than cure. A small cracked tile or a blocked valley can cause thousands of dollars of damage to ceilings, insulation, and framing if left unaddressed.

Safety First: Ground-Level vs On-Roof Inspection

Before you grab a ladder, understand the risks. Falls from roofs are a leading cause of serious injury in New Zealand. WorkSafe NZ recommends that homeowners carry out as much of their inspection as possible from the ground using binoculars, and from inside the roof space (ceiling cavity). If you do go onto the roof, use a properly secured ladder, wear non-slip footwear, never work alone, and avoid working in wet or windy conditions.

For steep-pitched roofs, multi-storey homes, or roofs with fragile materials (like older corrugated asbestos-cement), call a qualified roofer rather than attempting the inspection yourself.

Spring Roof Inspection Checklist

Work through this checklist methodically — from the ground, from inside the ceiling space, and (if safe) from the roof itself.

Ground-Level Checks

• Walk around the full perimeter of the house and scan the roof with binoculars
• Look for missing, cracked, or lifted tiles or sheets
• Check for sagging or uneven roof lines — these can indicate structural movement or rotten framing
• Inspect gutters and downpipes for blockages, rust, sagging, or sections that have pulled away from the fascia
• Look for moss, lichen, or algae growth — common in shaded, damp NZ conditions — which holds moisture and accelerates deterioration
• Check that downpipes discharge correctly away from the foundation
• Look for debris accumulation in valleys and gutters (leaves, twigs, pine needles)

Ceiling Cavity / Roof Space Checks

• On a sunny day, enter the ceiling space and look for pinpricks of light coming through the roof — these indicate holes or gaps
• Check for water stains, damp insulation, or mould on the underside of the roof cladding and on timber framing
• Inspect sarking or underlay (if present) for tears or sagging
• Check that roof ventilation is unobstructed
• Look for signs of pest activity — rats and possums can damage insulation and wiring

On-Roof Checks (if safe to do so)

• Inspect flashings around chimneys, skylights, vents, and parapet walls — these are the most common source of leaks
• Check ridge capping for cracked mortar or lifted sections
• On metal roofs, look for rust spots, lifted screws, or cracked sealant at laps and penetrations
• On tiled roofs, check for slipped, cracked, or broken tiles
• On membrane or flat roofs, look for blistering, cracking, or ponding water areas
• Inspect skylights for cracked glazing or deteriorated seals

Season-by-Season Maintenance Overview

Common Mistakes Homeowners Make

• Ignoring moss and lichen — these organisms physically lift roofing materials over time. Treat with a purpose-made roof wash product and consider a zinc or copper strip at the ridge to inhibit regrowth.
• Cleaning gutters but forgetting valleys — roof valleys channel enormous volumes of water and block just as easily as gutters.
• Using a pressure washer on tiles — high pressure can dislodge mortar and force water under tiles. Use low pressure or hand-brush methods.
• Repointing ridge capping with standard cement — use a flexible, purpose-made roofing mortar or bedding compound. Rigid cement cracks with thermal movement.
• Assuming a small stain on the ceiling is minor — by the time you see a stain inside, water has often been tracking through the structure for some time.
• Delaying repairs — a missing tile or cracked flashing left through summer will almost certainly cause a leak when the autumn rains arrive.

DIY vs Professional: What Can You Do Yourself?

Homeowners can safely carry out:

• Ground-level and ceiling-space visual inspections
• Clearing gutters and downpipes (with appropriate ladder safety)
• Applying moss and lichen treatment products
• Minor gutter realignment and resealing of gutter joints

Leave the following to a qualified, experienced roofer:

• Any work on steep or high roofs
• Flashing repairs and replacements
• Re-bedding and repointing ridge capping
• Replacing roof cladding or membrane sections
• Any work near electrical service lines

Note: Roofing work itself is not a licensed trade in NZ in the same way as electrical or plumbing, but electrical work near the roof (such as solar panels, heat pumps, or any wiring) must be carried out by a registered electrician under the Electrical Workers Registration Board. Similarly, any plumbing connections to roof drainage must comply with the NZ Building Code and may require a licensed drainlayer — check with the Plumbers, Gasfitters and Drainlayers Board.

For peace of mind, look for a roofer who is a Licensed Building Practitioner — LBPs are authorised to carry out and supervise restricted building work, and their work is recorded.

When to Call a Professional

Call a qualified roofer promptly if you find:

• Active leaks or fresh water staining inside the ceiling
• Sagging or deflection in the roof line
• Multiple missing or broken tiles or sheets
• Deteriorated or lifted flashings — especially around chimneys and skylights
• Significant moss or lichen coverage requiring professional treatment and possible recoating
• Any roof over two storeys or with a pitch too steep to safely walk
• Suspected asbestos-cement roofing (common in homes built before the 1990s) — do not disturb; seek specialist advice

You can find qualified, local roofing professionals on tradedirectory.co.nz — search by region to get someone familiar with your local conditions, whether that's Northland's humidity, Wellington's wind, or Canterbury's frost.

Sources & Further Reading

• BRANZ – Building Research Association of NZ
• MBIE Building Performance – NZ Building Code guidance
• WorkSafe NZ – Working at Height safety
• Licensed Building Practitioners – find or verify an LBP
• Consumer NZ – home maintenance advice
• Energywise – roof insulation and weathertightness