Solar on Perth homes with fibro or asbestos cement roofing

Many older Perth homes — particularly those built in the 1950s, 1960s, and 1970s in suburbs like Armadale, Gosnells, Midland, Rockingham, Kelmscott, and southern corridor development areas — have roofing made from fibro cement or asbestos cement (AC) sheeting. If you own one of these homes and are considering solar, the roof material matters significantly.

Identifying asbestos cement roofing

Asbestos cement roofing sheeting is typically flat or lightly corrugated, grey or weathered grey-brown in colour, and usually installed in overlapping sheets. Common trade names include Hardiflex, Hardie cement, and Super Six corrugated sheeting.

How to tell fibro from modern fibre cement: Modern James Hardie products (post-1987) are asbestos-free — genuine fibro from this era may look similar but contains no asbestos. Older pre-1987 products may contain chrysotile (white asbestos). If your home was built before 1985 and the roof appears to be cement sheeting rather than Colorbond or tiles, assume it may contain asbestos until professionally assessed.

Professional assessment: Before drilling, cutting, or disturbing any suspected asbestos cement sheeting, have a licensed asbestos assessor test a sample. In WA, the Department of Mines, Industry Regulation and Safety (DMIRS) regulates asbestos removal and assessment. Testing a roof sample costs $100–$250.

Can solar be installed on an asbestos cement roof?

Yes — but with significant caveats and additional cost.

Key constraint: no drilling through the sheeting. Asbestos cement that's intact and undisturbed is relatively safe — it becomes hazardous when cut, drilled, or broken (releasing fibres into the air). Traditional solar racking systems that bolt through the roof are not acceptable on intact asbestos cement roofing. Every penetration is both a hazard risk and a roof leak point.

Available mounting options:

Saddle clamps over ridges: Some racking systems clamp to the corrugated ridges of AC sheeting without penetrating the sheet. Load is transferred through the clamps and down to the structure beneath. This requires careful structural assessment to confirm the sheeting and battens can carry the panel load.

Independent roof frame: A freestanding frame structure built over (but not attached to) the asbestos roof distributes panel load to the fascia or wall structure rather than through the roof sheeting. More expensive ($3,000–$8,000 additional) but avoids roof penetrations entirely.

Roof replacement first: The cleanest path. Replace the asbestos cement roofing with Colorbond or concrete tiles (typically $15,000–$35,000 for a full Perth home roof replacement), then install solar on the new roof using standard mounting. This eliminates ongoing asbestos management obligations and provides a long-term stable solar platform.

Asbestos management obligations in WA

If your property has asbestos cement roofing and you disturb it (including during solar installation), WA law requires:

• Class A licensed removalist for any asbestos removal involving more than 10m²
• Friable vs non-friable: AC roofing that is intact is typically non-friable (bonded asbestos). Weathered, crumbling, or damaged sheets may become friable and require stricter handling
• Notification to DMIRS for removal above specified thresholds
• Disposal: Asbestos material must be double-bagged and disposed of at a licensed facility (Mindarie Regional Council tip accepts AC materials; other sites may vary)

A solar installer who proposes to drill through an asbestos cement roof without specialist handling procedures is not compliant with WA workplace health and safety law. Any reputable Perth solar installer will refuse to drill AC sheeting or will insist on licensed asbestos management throughout the process.

The roofing decision point

For many Perth homeowners with intact AC roofing who want solar, the practical choice is between:

A: Replace roof, then solar

• Full roof replacement (~$15,000–$35,000) + solar (~$9,000–$14,000) = combined project ~$25,000–$50,000
• Eliminates all future asbestos obligations
• New Colorbond roof has 36-year warranty
• Standard solar racking, no specialist mounting required

B: Non-penetrating solar mounting on existing AC roof

• Specialist racking ($3,000–$8,000 premium over standard installation) + solar
• Asbestos roof remains in place — ongoing management obligation
• Not suitable if AC sheeting is already damaged or friable
• Lower upfront cost than full roof replacement

C: Ground mount

• No roof penetrations
• Requires sufficient ground area (unshaded), council assessment for setbacks and height
• Higher system cost than rooftop

Most Perth solar installers can't install on AC roofing themselves — they'll refer you to a specialist or require roof replacement first.

Insurance implications

Some Perth home insurers have specific conditions around properties with asbestos cement roofing — particularly around coverage for roof damage claims. Before proceeding with any solar installation approach, notify your insurer of the roof type and proposed work. Failure to notify can potentially affect claims relating to roof damage.

Solar can be installed on Perth homes with asbestos cement roofing, but drilling through the sheeting is not permitted under WA safety law. Non-penetrating mounting systems add $3,000–$8,000 to installation cost. For many homeowners, replacing the AC roof with Colorbond before solar installation is the most practical combined approach — eliminating asbestos obligations and providing a standard platform for solar.