Aluminium foil tape is a self-adhesive tape with a thin aluminium backing. It’s commonly used to seal seams in ventilation ducting, cover joints between foil-faced insulation boards and join the outer facing on insulated pipework. The right tape depends on the surface, the width needed to cover the seam and the conditions the tape will face once installed.
If you’re buying for a job, start with two measurements. Find out how wide the tape needs to be, then add up the total length of the seams. Our aluminium foil tape collection includes a 48mm x 45m Bond It roll for longer runs and a 50mm x 10m Ultratape roll for shorter jobs. Both are listed as single rolls and in boxes.
What is aluminium foil tape used for?
Sealing ventilation ducting seams
Aluminium foil tape can be used over seams and connections in ventilation ducting where the system manufacturer specifies a compatible foil tape. Typical jobs include sealing a seam on a metal duct section or finishing an approved connection after the duct has been assembled.
Check how the duct sections must be joined before taping. The system instructions may call for a clamp, mechanical fixing, sealant or a combination of these. Apply the tape as part of that specified joint. On a circular connection, measure around the duct and allow for the overlap required by the installation instructions.
Joining foil-faced insulation boards
Where the insulation system calls for taped joints, aluminium foil tape can cover the seam between adjacent foil-faced boards. This is a common use on foil-faced PIR insulation. The tape should sit flat against the facing on both sides of the joint so that it has a continuous surface to bond to.
Before applying the tape, check that the boards are properly fitted and that the facing is clean and intact. Follow the insulation manufacturer’s instructions for handling gaps, damaged facing and junctions at corners. These details matter if the taped joints form part of a specified air barrier or vapour control layer.
Finishing foil-faced pipe lagging
Compatible foil tape can also be used to close seams in the outer foil facing of pipe insulation. The tape goes onto the facing, so check that it can bond to that material and tolerate the temperature and moisture conditions at the seam. Pay particular attention to joints around bends and fittings, where the facing may be uneven.
If you’re ordering for a maintenance team, it helps to list the surfaces and systems the tape will be used on. Two jobs can look similar on an order sheet and still require different tape specifications.
How to choose the right aluminium foil tape
1. Check the surface and installation requirements
Start with the ducting or insulation manufacturer’s instructions. Look for the specified tape type, compatible surfaces, minimum width and any required overlap. If the job specification names a product or approval, check the technical data for the exact roll you plan to order.
The surface can affect how well a tape sticks. Smooth sheet metal, embossed foil facing and foil around a curved fitting each give the adhesive a different area of contact. Inspect the surface where the tape will actually sit, especially if you’re working on an existing installation with dust, old adhesive or damaged facing.
2. Choose a width that covers the seam
The tape needs enough room to bond securely on both sides. As a simple example, a 50mm tape centred on a 10mm-wide seam leaves about 20mm of tape on each side. Whether that is enough depends on the installation requirements and the condition of the surrounding surface.
The 48mm and 50mm rolls in our range are close in width. If your specification calls for a minimum of 50mm, choose a roll that meets that minimum and the rest of the specification. If the seam needs wider coverage, measure the total width required before ordering.
3. Match the roll length to the job
A 10m roll is practical when you have a few short seams to cover or want compact rolls for service kits. A 45m roll provides more tape for longer duct runs, several boards or work across multiple rooms. On a long run, it also reduces the number of times you need to stop and start a fresh roll.
Estimate the length before comparing pack prices. A small roll can suit a one-off repair, while a box can make more sense for a team carrying out similar work each week. Allow for corners, joins, offcuts and any extra tape needed around fittings.
4. Check temperature, exposure and any required rating
Look up two figures in the product’s technical data. The application temperature tells you the conditions in which the tape can be fitted. The service temperature tells you the conditions it can handle after installation. That distinction matters when you’re applying tape in a cold loft, on an exposed site or around equipment that warms up during use.
If the installation requires a particular fire classification or outdoor performance, verify it for the exact tape. Consider how much sunlight, rain or condensation the joint will see and whether it will be sheltered once the work is complete.
Bond It vs Ultratape foil tape
The clearest difference between these two rolls is length. Bond It gives you 45m per roll, while Ultratape gives you 10m. Both come in single-roll and box options, so you can choose a pack based on how the tape will be used across your jobs.
| Product | Roll size | Listed pack options | When to consider it |
|---|---|---|---|
| Bond It Aluminium Foil Tape | 48mm x 45m | Single roll or box of 24 | Longer duct runs, multiple insulation seams and repeat work. It has a 30-micron aluminium backing. |
| Ultratape Aluminium Foil Tape | 50mm x 10m | Single roll or box of 12 | Smaller jobs, short sections of ducting and maintenance kits. It is listed for compatible HVAC and foil-faced insulation applications. |
A full box of Bond It contains 1,080 metres of tape across 24 rolls. A full box of Ultratape contains 120 metres across 12 rolls. If you’re stocking vans or tool kits, consider how many rolls you’ll need to distribute as well as how many metres you’ll use. Check each product page for current pack prices and availability.
How much aluminium foil tape do you need?
Measure the seams you plan to cover and add their lengths together. For round duct joints, measure around the outside of each connection. Include any corners, returns and overlaps required by the installation instructions. Keeping a simple list by room, duct run or board section makes it easier to spot joints you might otherwise miss.
Suppose you have 18m of seams before allowing for waste and overlap. Two 10m rolls give you 20m in total, leaving 2m to spare. One 45m roll gives you enough for the same run with 27m left for other work, before accounting for waste and overlap. A contractor with more joints to finish might use the longer roll, while someone working on a single job may prefer two shorter rolls if the allowance is enough.
When comparing prices, divide the pack price by the total number of metres in the pack. Compare both prices on the same VAT basis and factor in any delivery charges that apply to the order. For a trade buyer, that gives a clearer comparison than the price per roll alone.
How to apply aluminium foil tape
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Prepare the joint. Check that the duct or insulation is fitted as specified. Remove dust, grease and moisture from the surfaces that will receive the tape. Use a cleaning method suitable for the material.
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Measure and position the tape. Allow for any required overlap and centre the tape over the seam. Check that it has enough contact on both sides, particularly at corners and changes in direction.
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Peel the liner back as you go. If the roll has a release liner, peel back a short section to get started. Work along the seam in manageable lengths so you can keep the tape aligned.
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Press it down firmly. Smooth from the centre towards the edges. Use a suitable applicator if recommended, especially on long, flat joints. Pay attention to the edges, where lifted tape is easiest to miss.
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Inspect the finished seam. Check for exposed sections, creases across the joint and areas where the tape has lifted. Rework any section that has poor contact in line with the system instructions.
For an existing installation, take a close look at the joint before covering it. If the duct connection moves or the foil facing is peeling, repair that part of the installation first. The tape needs a stable surface to bond to.
Common mistakes when buying foil tape
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Ordering by length alone. A 45m roll can cover a long run, but it still needs to be wide enough for the seam. Confirm the minimum width before comparing pack prices.
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Assuming similar-looking rolls have the same specification. Two silver foil tapes can have different adhesives, temperature ranges and approvals. Check the exact product details for the job.
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Counting only straight seams. Curves, corners, overlaps and offcuts all use tape. Add them to your estimate before deciding how many rolls to buy.
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Applying tape to dusty or damp surfaces. A quick clean and inspection can help you spot areas where the tape may have poor contact. Check that the surface is dry and within the product’s application temperature range.
Frequently asked questions
Can you use aluminium foil tape on PIR insulation boards?
Yes, where the PIR boards have a compatible foil facing and the insulation manufacturer specifies taped joints. Follow the board system’s requirements for tape width, overlap and surface preparation. Check the instructions for corners and gaps too, as these may need a different detail from a straight joint.
Is aluminium foil tape the same as duct tape?
Aluminium foil tape has a metal backing. Standard cloth duct tape has a fabric-reinforced backing. Some foil tapes are sold as HVAC duct sealing tape because they’re designed for specific ventilation applications. Use the type and grade specified for your ducting system.
Is aluminium foil tape waterproof?
Water resistance depends on the exact tape and the finished joint. Check the manufacturer’s specification for rain, condensation or continuous water exposure. Where the job requires a waterproof system, follow the specified sealing method for that system.
Can aluminium foil tape be used outdoors in the UK?
Some grades are listed for exterior use. Check the product’s suitability for the level of weather exposure and the surfaces involved. During fitting, also check that the surface is dry and that the temperature falls within the recommended application range.
What does 30-micron aluminium foil tape mean?
It means the aluminium backing is 30 microns thick, or 0.03mm. On the Bond It roll, that figure describes the foil itself. When comparing two tapes, also check the adhesive, intended use and product specifications.
Should I buy 10m or 45m aluminium foil tape?
Choose a 10m roll if it covers your measured seams, including overlaps and offcuts. A 45m roll is worth considering for longer runs, several rooms or regular maintenance work. Check the required width and product suitability before choosing the length.
Where can I buy aluminium foil tape in bulk in the UK?
Tapes Wholesale is a tape supplier based in Cheetham Hill, Manchester. You can browse single rolls and trade boxes in the foil tapes collection. For a bulk order or help comparing pack options, send your required width, estimated quantity and delivery postcode through our contact page.