Sourcing double-glazed units from China

0% duty

Read from the UK Trade Tariff on 26 September 2026, multiple-walled insulating units of glass, heading 7008, carried 0% on goods from China on all three lines, with no anti-dumping measure: units of tinted, opacified, flashed or coated glass, units of two panes sealed around the edge with an air layer, and other units such as triple glazing.

Single panes of toughened or laminated glass fall under heading 7007 (see our toughened and laminated glass guide), and complete windows with frames are classified by the frame material. Confirm the commodity code from what you actually ship.

Construction product rules

Insulating glass units are covered by a harmonised standard, BS EN 1279-5, so under the retained Construction Products Regulation the manufacturer issues a declaration of performance and marks the units. Ask for the declaration, the initial type test reports and the factory production control certificate before ordering.

In buildings, the Building Regulations 2010 set energy performance for windows and require safety glazing in critical locations, so the glass make-up of each unit, such as toughened or laminated panes, has to match where it will be fitted.

Specifying units

Specify the glass make-up pane by pane (thickness, toughened or laminated, low-emissivity coating and which face), spacer type and colour, gas fill, overall thickness, size tolerances, edge seal system, centre-pane U-value, and any labels or stamps the fabricator needs. Send a cutting list with every size, because units are made to order.

Worked duty example

An invented example rather than a quote: 1,200 double-glazed sealed units, commodity code 7008 00 81 00, bought for £36,000 free on board, with £6,000 of freight and insurance, so £42,000 is the value customs works from. No duty is due on double-glazed units; import VAT at 20% of £42,000 is £8,400. If you are VAT-registered, that VAT is normally reclaimable. See calculating UK import duty and VAT for the method.

Inspection checklist

Seal durability: ask for the moisture penetration and gas leakage test reports to BS EN 1279-2 and BS EN 1279-3 for the edge seal system used, and check the spacer and sealants match those reports.

Dimensions and make-up: measure sampled units against the cutting list, check overall thickness, and check the low-emissivity coating is on the specified face and the safety panes carry their marks.

Visual and packing: check units for scratches, inclusions and sealant faults in daylight at the viewing distance agreed in the order, and check units stand on edge in A-frames or crates with spacers and corner protection.

What goes wrong

Double-glazed units fail on seals, sizes and breakage. Poor edge seals let moisture in so units mist between the panes within a few years, units arrive a few millimetres out and do not fit the frames, low-emissivity coatings face the wrong way, and units crack in transit because crates were not braced or units lay flat.

Agree the seal system and test evidence before production, measure every size on samples, and check crating before loading. See our quality inspection guide.

Cambridge China Bridge sources double-glazed units for window fabricators, conservatory builders and contractors, and can place a first order to test sizes and seals. See small orders.