Can we get samples before placing a bulk order?

Yes. Sample rolls ship by courier so your team can handle the product, check the print and run it on a test deck before you commit. Tell us which series and grammage you want to evaluate and we will arrange the shipment.

Can you print our own brand on the roll?

Yes — private-label printing is a standard part of the programme. Your logo, lap and nailing guides, contact line and safety wording can all be printed in line during production. Print plates and minimum quantities are confirmed per item.

What is the minimum order quantity?

Minimum order is one pallet (56 rolls), on any specification, for both factory-direct and US warehouse shipments. Send us your target roll spec — width, length, grammage and print — and we will confirm the MOQ for that item.

Do you supply test reports with each shipment?

Yes. Test reports are issued per order and travel with the shipping documents. If your market requires third-party testing or a specific standard, raise it at quotation stage so the test plan is agreed before production begins.

Can we audit the factory or send a third-party inspector?

Both are welcome by appointment. Let us know the scope — checklist, standard or customer requirement — and we will have the relevant batch records and production staff available on the day. Remote video walk-throughs can also be arranged.

Which markets do you export to?

We supply distributors, contractors and private-label partners across North America, Europe and Asia-Pacific, with selected lines held in US and EU warehouse stock. Contact the sales desk to confirm current availability for your destination.

Code & Practice

Roof Slope and Underlayment Layers: Single vs Double Coverage

Underlayment layer count is not a preference — it is tied to roof slope, and the thresholds are specific. Getting this wrong affects both code compliance and how much material a project actually consumes. Here is how the rule works and what it means for ordering.

The rule

The two slope thresholds

Roof slope	Required coverage	Key lap requirements
4:12 and steeper	Single layer	Horizontal laps at least 2 in; end laps at least 4 in
2:12 up to 4:12	Double layer	19 in starter strip at the eave, then 36 in sheets overlapped 19 in, leaving 17 in exposed
Below 2:12	Not a shingle application	Shingles are not permitted; a low-slope membrane system is used instead

The logic is straightforward: steeper roofs shed water faster, so water spends less time on the underlayment surface and the risk of penetration at a lap seam is lower. Shallower roofs hold water longer and need redundancy.

Method

How the double-layer application is built

Apply a 19-inch starter strip along the eave edge first.
Lay a full 36-inch sheet over it, aligned to the eave.
Each subsequent 36-inch sheet overlaps the one before by 19 inches, which leaves 17 inches exposed.
That pattern produces two layers of felt at every point on the roof surface.
The alternative allowed in most codes is a single layer of self-adhered modified bitumen across the whole low-slope section — faster to install, better water resistance, higher material cost.

Ordering

What this means for material quantity

A double-layer roof consumes roughly twice the underlayment of a single-layer roof of the same plan area, before waste. On a project with mixed slopes — a steep main roof with a shallow porch or dormer — the shallow sections drive extra material that is easy to miss in a take-off.

Measure each slope zone separately rather than applying one factor to the whole roof.
Add waste for valleys, penetrations and complex geometry; 10 percent is a common starting allowance for simple roofs, more for complex ones.
Remember that roll coverage varies by product — a lightweight synthetic roll covers several times the area of a 30 lb felt roll at a fraction of the weight, so roll counts and square counts diverge.

Buyer note roll weight drives both freight cost and crew handling. A synthetic roll covering roughly ten squares typically weighs far less than the equivalent coverage in 15 lb felt, which changes pallet counts, container loading and labour per square.

FAQ

Common questions

Where exactly is slope measured?

Slope is rise over run — inches of vertical rise per 12 inches of horizontal run. A 4:12 roof rises four inches for every twelve inches of horizontal distance. It is measured on the roof plane, not on the plan drawing.

Does a synthetic underlayment need two layers on a 3:12 roof?

The layer requirement in the code is written against the assembly, not the material type, so a mechanically fastened synthetic sheet on a 2:12 to 4:12 roof is generally still applied in the double-layer pattern — or replaced with a single layer of self-adhered membrane. Confirm with the authority having jurisdiction, since products with an evaluation report may carry alternative approvals.

Can one layer of ice and water shield substitute for two layers of felt?

In most codes, yes — a single layer of self-adhered modified bitumen membrane over the entire low-slope section is an accepted alternative to the double-layer felt application. It costs more per square but installs faster and provides continuous waterproofing rather than two lapped layers.

Need the spec sheet behind the claim?

Tell us the product, roll spec and destination. We will send the current data sheet, test reports and a quotation against your actual requirement.

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