Warranty

How many years — all categories

Our principle is simple: what is our own workmanship, we warrant for 5 years. What depends on other factors — the material grade you choose, or a design you supply — we state exactly as it is.

When you report a claim, we inspect the site within 7 days of notification.

1. Workmanship and leak-proofing — 5 years

Leaks caused by installation are entirely controllable through correct working method. Done right the first time, it does not leak later. That is why we warrant our own workmanship for a full 5 years — materials excluded, as those follow the grade selected.

• Leaks at fasteners — loose or withdrawn screws, wrong placement, washers damaged by incorrect torque
• Leaks at sheet laps — insufficient overlap or laps not sealed by the correct method
• Leaks at ridge caps, flashings and wall abutments
• Sheet deflection caused by purlin spacing that we specified
• Sheets shifting or lifting due to substandard fixing
• Gutter leaks arising from our installation

Condition — the roof must be built to the specification we recommend

Leak performance depends directly on roof pitch and purlin spacing relative to sheet thickness. Too little pitch and water backs up through the laps; purlins spaced wider than the sheet can carry cause permanent deflection, which reduces the effective pitch and widens the screw holes until water enters.

The standard we work to: minimum pitch of 5 degrees (3 degrees for click-lock profiles), and purlin spacing per the manufacturer’s table for the sheet thickness actually used. Both are stated in the quotation for each project.

If you ask us to reduce the pitch, widen the purlin spacing, use fewer purlins, or fit a thinner sheet than we recommend, we are happy to build it that way — but in that case we cannot warrant against leaks, because the outcome follows from the reduced specification, not from our workmanship. We tell you and record it in the quotation before work begins.

2. Roof penetrations — 5 years, only where we did the work

Holes cut through a roof are the single most common source of leaks — more so than the sheet itself. Penetrations include air-conditioning lines and refrigerant pipes, kitchen extract ducts, vent stacks, waste pipes, skylights, antennas and solar mounting brackets.

• Penetrations we install — formed with proper weatherproofing components, never a bead of silicone over the hole. Warranted 5 years, the same as our workmanship.
• Penetrations cut later by others — air-conditioning, solar, kitchen or cabling contractors. The warranty ends, including any damage that spreads from that point.
• Other trades working on the roof without laying walk boards — this dents the sheet and creates ponding hollows that lead to leaks. The warranty ends in the same way. Anyone going onto the roof must lay boards to spread their weight.
• Tell us before anything is cut or anyone goes up — we will form the penetration correctly, or brief your contractor on the correct method, at no charge. That is far better than discovering a leak afterwards.
• Roofs over kitchens are a special case — they combine an extract duct through the roof with cooking grease and heat settling on the sheet every day, which attacks the coating far faster than normal. For this type of work we assess the site first and state the warranty period for that project separately in the quotation.

3. Structural integrity of steelwork — 5 years with engineered design

What allows us to warrant structural integrity is not workmanship alone, but calculations for which an engineer takes responsibility.

We draw the line this way because workmanship is always our responsibility, while the adequacy of a design belongs to whoever designed it. If you want full 5-year structural cover, tell us at quotation stage and we will arrange engineered design and calculations.

4. Anti-rust coating on steelwork — 3 years

Protective coating applied to steel structures carries a 3-year warranty, covering surface rust arising from our surface preparation and paint application.

This excludes structures in particularly corrosive environments — coastal locations, livestock housing, or areas with chemical vapour — which are assessed individually with the period stated in that project’s quotation.

5. Sheets and sheet coating — by grade selected

Our principle: we never promise more than the sheet manufacturer promises. Everything follows the manufacturer’s warranty document for that product.

• BlueScope sheets (manufacturer’s warranty provided) — warranted fully in line with the manufacturer’s terms, typically 10–30 years depending on product, coating mass and paint system. When a qualifying issue arises, we file the claim with the manufacturer on your behalf; you do not deal with them yourself. We keep the product, batch and documentation on file from the day of installation.
• Imported or commodity-grade sheets (no manufacturer’s warranty) — we warrant the sheet ourselves for 2 years. You are free to choose an economical sheet, and we state clearly in the quotation which grade is used and how long it is warranted.

Please note: a manufacturer’s warranty carries its own conditions, such as distance from the sea, roof pitch and installation method — if those conditions are breached the warranty is void, both theirs and ours.

6. Fixings and insulation — warranty scales with the specification chosen

A roof is more than sheets and steel. Fixings and insulation vary enormously in durability depending on what is specified, so we warrant them according to what is actually installed.

Fibre cement and composite boards perform very well indoors, but exposed directly to sun and rain their service life shortens noticeably. The warranty period also depends on the board thickness selected. For external work we usually recommend materials better suited to the weather, and we will put those options in front of you at quotation stage.

Why PE insulation carries a shorter warranty: PE sheet is bonded to the roof with adhesive. Under daily cycles of trapped heat and rain-borne moisture the adhesive degrades quickly and the insulation falls away. That is the nature of the material rather than a defect in installation — PU at 25 mm bonds and resists heat far better, so it can be warranted for longer.

The quotation always states which specifications we set and which you selected, together with the warranty period for each part. You may choose the economical option, but you will see before signing exactly what is being traded away.

7. Repairs to an existing roof — 3 to 5 years by method

Repairs do not all carry the same warranty, because the methods are fundamentally different. Sealing a leak treats the symptom; fixing the root cause is what stops it coming back.

We tell you at quotation stage which method your roof needs and how long it is warranted. If you choose sealing to save cost we will carry it out, but you should know the warranty is shorter, because the underlying cause remains.

Before we can warrant a repair, we must inspect the existing roof

• The existing roof pitch — below the minimum, repairing one point may simply move the leak elsewhere, because the pitch is the cause rather than the point that leaked
• Existing purlin spacing and sheet thickness — if the purlins are wider apart than the sheet can carry, it will deflect and leak again no matter how well the repair is done
• Condition of the existing structure — rust, decay, existing welds, settlement, because we are fixing new work onto it

The inspection findings are attached to the quotation. If these cannot be established, we will still carry out the repair, but we will not be able to issue a warranty, and we will say so before work starts.

What ends the warranty

Our installation workmanship remains our responsibility throughout, whatever material specification you choose.

Not covered by the warranty

• Natural events beyond the design criteria — storms, hail, earthquake, flooding, falling trees
• Physical damage — walking on the wrong part of the roof, or heavy objects dropped onto it
• Corrosive site conditions not disclosed to us at quotation stage
• Work that is not ours — the existing structure, existing purlins or existing walls in repair and extension work
• Lack of maintenance — allowing leaves or silt to block gutters until water backs up under the roof
• Sealing the drainage channel with silicone — that channel exists to drain water; blocking it traps moisture and attacks the sheet from beneath
• Colour fading through normal service life, as distinct from paint peeling or flaking away

Work that requires a site assessment first

Certain site conditions directly affect the life of the coating and paint, and sheet manufacturers apply their own conditions to them as well:

• Coastal locations
• Livestock housing
• Factories with chemical vapour
• Roofs over kitchens, exposed to grease and heat
• Any other site-specific risk we find during assessment

For work of this kind we assess each project individually and state that project’s warranty period in the quotation, which may be shorter than our standard terms. We would rather say so plainly at the start than quote an attractive figure and fall out over it later.

How to make a claim

• Contact us on LINE with photographs of the affected area and the handover date or job number
• We inspect the site within 7 days of your notification
• We schedule the repair with you immediately after the inspection, with the date set by the size of the job and material lead time. We deliberately do not promise a fixed number of days for the repair itself, because matching sheets to the original profile and colour takes varying time
• Within the warranty terms there is no charge. If the inspection shows the issue falls outside the terms, we always tell you the price before proceeding

General terms

• The warranty period runs from the date of handover
• The terms on this page are our standard terms. The terms and periods for your project are those stated in the quotation for that project.
• We may update this page from time to time to reflect how we actually work. Updates do not apply retrospectively to work already agreed — the terms for your project are those stated in its quotation.

Questions about the warranty

Ask us before you decide — there is no charge for that.

The Metal Sheet Co., Ltd.
Tel. 088-850-6314
Email [email protected]

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