How long until my sealed unit ships?

Standard double-glazed units take 5–7 working days to make and dispatch. Triple-glazed, toughened and laminated units take 10–14 working days. We email you your delivery day the day before.

What warranty do you offer?

Every sealed unit carries a 10-year guarantee against seal failure (condensation between panes) and structural defects. Our fitting work and coatings (Low-E, self-cleaning, solar) are also guaranteed for 10 years. The guarantee covers the original buyer only and doesn't transfer to a new owner.

Are you FENSA registered?

Yes. Pane Relief is FENSA registered for installation work, installer number 43465. FENSA registration confirms our installations comply with Building Regulations Document L (energy efficiency).

What dimensions do I provide?

Measure the visible glass (not the frame), then add 25mm to the width and 25mm to the height, in millimetres.

Do you deliver UK-wide?

Yes, anywhere on mainland UK. Delivery is free to Bristol (BS) postcodes. Everywhere else on the UK mainland it costs £150 + VAT (£180), with no free-delivery threshold. The largest unit we deliver is 2900mm × 1500mm, with a £15 surcharge on any unit over 2000mm.

What postcodes do you cover for installation?

Bristol, Bath, North Somerset and South Gloucestershire, plus Gloucester and towns in Wiltshire and Somerset. Elsewhere on the UK mainland we supply units for you or your installer to fit.

What payment terms do you offer?

We don't offer 30-day credit terms.

Can I return a sealed unit if I measured wrong?

Made-to-measure sealed units can't be returned unless faulty or damaged. If you measured wrongly, we remake the unit and you pay the same price again. You can change or cancel free of charge until production starts. Please report any damage within 24 hours of delivery.

What's the difference between a sealed unit and replacement glass?

A sealed unit is a complete double-glazed assembly: two panes of glass bonded around a spacer bar with desiccant, with air or (as an upgrade) argon gas between the panes. Replacement glass is a single pane. If your unit is misted, you need a new sealed unit, not just glass.

Are your units BS EN 1279 compliant?

Yes. Every Pane Relief sealed unit is made by our partner factory to BS EN 1279, the European durability standard for insulated glass units. This covers gas concentration retention, edge seal integrity, and moisture penetration.

Yes. Apply for a trade account at panerelief.co.uk/pages/bulk-orders. Trade discounts are 5% at 5+ units, 10% at 20+ and 15% at 50+. We don't offer 30-day credit terms.

How do I measure a sealed unit?

Measure the visible glass face, width and height, in millimetres, then add 25mm to the width and 25mm to the height. That is your order size. Our measuring guide: panerelief.co.uk/pages/measuring-guide

Can I measure from outside?

We recommend measuring from inside for safety and access. You'll need to remove a bead section to measure thickness, which is easier from inside. The measurements should be identical from either side, but interior access is more practical.

What if my measurements are wrong?

If sealed units arrive and don't fit, we'll manufacture replacements at a discounted rate. However, toughened glass cannot be resized after manufacture — it must be remade. This is why we strongly recommend measuring twice and contacting us to verify before ordering.

Can I send you my measurements to check?

Yes, and we encourage it. Email your measurements and photos to us before placing your order. We'll review them and flag any concerns. This free check has saved many customers from ordering incorrectly sized units.

Do I need to measure each window separately?

Yes. Even windows that look identical may have slightly different glass sizes due to manufacturing tolerances in the frames. Measure each window individually and label your measurements clearly (room, position, width × height × thickness).

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Step-by-Step Guide

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Measuring Guide

Name: Pane Relief
Address: 36 Saltmarsh Drive, Bristol, South West England, BS11 0NG, GB
Telephone: 0117 330 3057
Price range: ££
Rating: 4.4

Accurate measurements are essential for a perfect fit. Follow our step-by-step guide to measure your existing frames for replacement sealed units.

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Easy to Follow

Millimetre Accuracy

Help Available

Tape Measure

A metal tape measure accurate to the nearest millimetre. Cloth tapes stretch and are not accurate enough for glazing measurements.

Pen and Paper

Record each measurement immediately. Note which window each measurement refers to — label them by room and position (e.g. 'Kitchen left').

Step Ladder

You may need to reach the top of larger windows to measure height accurately. Always measure from inside the property for safety.

Phone (Camera)

Take photos of each window you're measuring. This helps us identify any non-standard configurations and advise on specification.

Expert Knowledge

How to Measure for Replacement Sealed Units

Important: You're measuring the glass, not the frame. Replacement sealed units fit into your existing frame rebate, so we need the glass dimensions, not the overall window size.

Step 1: Measure the width

Measure the width of the visible glass from edge to edge. Record in millimetres.

Step 2: Measure the height

Measure the height of the visible glass from edge to edge. Record in millimetres.

Step 3: Add 25mm to each

Add 25mm to the width and 25mm to the height. So if your visible glass measures 590mm × 1190mm, order 615mm × 1215mm. If a unit is made to a wrong measurement, we remake it and you pay the same price again, so please double-check.

Step 4: Measure the thickness

Remove a bead (the strip holding the glass in place) to expose the edge of the sealed unit. Measure the total unit thickness with a ruler or callipers. Common thicknesses are 20mm (4/12/4), 24mm (4/16/4), and 28mm (4/20/4).

Step 5: Check for special shapes

If your window is arched, angled, or any shape other than rectangular, contact us with photos and measurements. We supply bespoke shapes to your exact specification.

The most common error is measuring the frame opening rather than the glass. The glass sits in a rebate behind the beading — it's smaller than the visible opening. Always remove a section of beading to see the actual glass edge before measuring.

We recommend measuring from inside for safety and access. You'll need to remove a bead section to measure thickness, which is easier from inside. The measurements should be identical from either side, but interior access is more practical.
If sealed units arrive and don't fit, we'll manufacture replacements at a discounted rate. However, toughened glass cannot be resized after manufacture — it must be remade. This is why we strongly recommend measuring twice and contacting us to verify before ordering.
Yes, and we encourage it. Email your measurements and photos to us before placing your order. We'll review them and flag any concerns. This free check has saved many customers from ordering incorrectly sized units.
Yes. Even windows that look identical may have slightly different glass sizes due to manufacturing tolerances in the frames. Measure each window individually and label your measurements clearly (room, position, width × height × thickness).

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