Healthy Homes Draught Stopping NZ: Gaps, Fireplaces and What to Seal

What Counts as an "Unreasonable" Gap

Regulations 25 and 26 require landlords to seal unreasonable gaps and holes in walls, ceilings, windows, doors, and floors that produce noticeable draughts. The standard does not require an airtight building — it targets the gaps that actually let cold air stream in and heated air escape.

Common draught sources in NZ rentals:

• Gaps around window and door frames where weather stripping has perished or was never installed
• Spaces under exterior doors with no threshold seal
• Gaps around pipes, cables, and ducts where they pass through exterior walls or floors
• Unsealed gaps where floorboards meet skirting
• Cracks or holes in walls from old fittings, removed hardware, or building movement
• Gaps around the ceiling hatch or manhole access

None of these require a specialist. Weather strip tape, expanding foam, silicone sealant, and brush-style door seals handle most residential draught-stopping work. The key is identifying every source and sealing it before you complete the compliance statement.

Open Fireplaces: Block or Seal

Open fireplaces are one of the biggest sources of heat loss in older NZ properties. Under the draught stopping standard, an open fireplace must be permanently blocked or fitted with a draught stopper.

The one exception: if the tenant requests in writing that the fireplace remain open, and the landlord agrees, the fireplace can stay unblocked. Without both the tenant's written request and the landlord's agreement, the fireplace must be sealed.

Options for blocking a fireplace:

• Chimney balloon or chimney sheep — an inflatable or wool plug inserted into the flue opening. Removable and relatively cheap ($30–$80). Effective as long as it maintains a seal
• Fireplace blanking plate — a rigid board or sheet metal panel fitted into the fireplace opening. More permanent than a balloon
• Permanent sealing — bricking up or plastering over the opening. The most effective, but only practical if the fireplace will never be used

If you use a removable draught stopper like a chimney balloon, check it between tenancies. They deflate over time and need replacing.

Safety Ventilation: What You Must Not Seal

Not every opening is a draught. Some are intentional safety vents that must stay open:

• Passive combustion air vents for flued gas heaters — blocking these creates a carbon monoxide risk
• Mandatory bathroom air bricks — required for ventilation in rooms without mechanical extraction
• Sub-floor ventilation grilles — these prevent moisture buildup under the building

Sealing a safety vent violates both the Healthy Homes Standards and the Building Code. If you are unsure whether an opening is a draught source or a safety vent, check what appliance or system it serves before sealing it.

Documenting Draught Stopping

Your compliance statement must declare the status of draught stopping across the property. Your evidence file should include:

• A list of identified gap sources and what was done to seal each one
• Dated photos showing sealed gaps, installed weather stripping, and blocked fireplaces
• Receipts for materials (weather strip, sealant, chimney balloon, blanking plate)
• If you agree to leave an open fireplace at the tenant's written request: keep the request and record your agreement

This is one of the cheapest standards to meet — materials are inexpensive and the work is straightforward — but it is also one of the easiest to overlook when completing the compliance statement.

The NZ Healthy Homes compliance guide walks through a room-by-room draught audit with the common gap sources for each room type and the evidence items to photograph.

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