The Bradford HVAC glasswool we stock is five products in two forms. Rigid board lines the inside of rectangular duct and holds its own shape. Flexible blanket wraps round duct and curved plant. Density is what separates them: Multitel 18 kg/m³, Flexitel 24, Supertel 32, Ultratel 48. Service temperature does not separate them at all, because every one is capped at 70°C once it is faced.
In short
- Board for rectangular duct, silencers and flat plant. Blanket for round duct, curved plant and wrapping.
- Bradford writes a separate technical statement for each, so nobody sets them side by side. The table below does.
- All five are 150°C unfaced and 70°C faced. Duct work is nearly always faced, so 70°C is the real ceiling.
- All five state they are not non-combustible to AS 1530.1 and do not meet AS 1668.1 clause 2.3.2. Stone wool is the place to look, though Bradford's stone wool statements claim non-combustibility and a fusion temperature, not 2.3.2.
- Multitel HVAC Blanket and Multitel BAL 12.5-40 Blanket share a name and are opposite on non-combustibility. Order by code.
Board or blanket, decided first
Everything else follows from the form. A rigid board stands up on its own, so it lines rectangular duct, goes into silencers, and sits on flat plant where the insulation has to hold a face rather than sag into it. A blanket comes off a roll, so it wraps round duct, elbows, curved plant and the outside of a rectangular run. Boards are sheets, 2400 x 1200 mm up to 3000 x 1500 mm. Blankets are rolls 1200 to 1500 mm wide.
Many jobs use both, an internal liner for noise and an external wrap for heat. Bradford says as much: Flexitel and Multitel "can also be used to supplement internal ductwork insulation to achieve higher R-values".
The five products, side by side
Five documents, one table, in density order. All five are rated 150°C unfaced and 70°C faced, so that column is left out.
| Product | Density | Bradford's stated application | Thickness and R range we stock | Facings in the statement |
|---|---|---|---|---|
| Multitel HVAC Blanket | 18 kg/m³ | External HVAC duct wrap | 25 mm at R0.6 to 75 mm at R2.0, plus 38 mm at R1.0, 50 mm at R1.3 and 55 mm at R1.5 | Plain, medium duty, heavy duty |
| Flexitel HVAC Blanket | 24 kg/m³ | Internal or external rigid duct lining | 25 mm at R0.65 to 75 mm at R2.1 | Plain, heavy duty |
| Supertel HVAC Blanket | 32 kg/m³ | Insulation for HVAC rigid ducts | 25 mm at R0.7 to 100 mm at R3.0 | Plain, Acoustituff, heavy duty, HDP, Ultraphon |
| Supertel HVAC Board | 32 kg/m³ | Internal insulation for HVAC rigid ducts | 25 mm at R0.7 to 100 mm at R3.0 | Plain, Acoustituff, Ultraphon, HDP |
| Ultratel HVAC Board | 48 kg/m³ | HVAC silencers and internal duct lining | 50 mm at R1.5, 75 mm at R2.3, 100 mm at R3.0 | Plain, Acoustituff, HDP |
Density is what you buy, not an R-value ladder: 75 mm of Multitel at R2.0 and 75 mm of Supertel at R2.2 are within a hair of each other. Our page calls Ultratel high compressive strength, but Bradford's documents do not. The 2020 selector describes Ultratel on sound absorption and rigidity, and nothing Bradford publishes gives a figure in kPa at any deformation. The only compression comparison it draws is between the blankets, that Flexitel has "higher compression resistance and tensile strength than Multitel". Density against R-value is in acoustic versus thermal insulation. None of these five is a building element product, so a partition, a midfloor or a plenum goes to acoustic batts by building element instead.
The 70 degree ceiling, and the clause that rules them out
Service temperature usually eliminates products from a plant room schedule. Here it eliminates nothing. All five print the same two lines: 150°C unfaced, 70°C faced. A liner or a wrap is almost always faced, so 70°C governs. The 2020 selector was more granular, 70°C for paper and plastic based facings and 100°C for glass woven, and the statements drop that split. Above 150°C, Bradford's glasswool answer is Thermatel at 480°C, which we do not stock.
The limit that does remove them appears word for word in all five. The product "does not meet the non-combustibility or fusion temperature requirements of AS 1668.1 - The use of ventilation and air conditioning in buildings, 2.3.2", and "is not classified as non-combustible in accordance with AS1530.1". If the specification cites 2.3.2, no thickness or facing will help, and Rockwool Fibertex and Fibermesh is where to go. Indices and Group numbers are in fire performance of insulation.
None of the five publishes a fire resistance level, and none is suitable as an exposed lining where a Group Number is required. The published figures are spread of flame and smoke developed to AS/NZS 1530.3: plain 0 and 1, every faced version 0 and 3. Bradford assessed insulation in a duct section to the UL-181 burning test, 25 to 100 mm for the boards and 25 to 75 mm for the blankets, calling that "an indicative test only" because AS 4254 requires the full assembly to be tested.
How thick, product by product
A contractor's question is how thick each product has to be to reach the same number. Bradford answered it in section 3.3 of its selector, the only place the three meet.
| Target material R-value | Supertel, internal liner | Multitel, external wrap | Flexitel, external wrap |
|---|---|---|---|
| RM1.2 | 40 mm, RM1.2 | 50 mm, RM1.3 | 50 mm, RM1.4 |
| RM1.6 | 63 mm, RM1.8 | 75 mm, RM2.0 | 75 mm, RM2.1 |
| RM2.0 | 67 mm at RM2.0, or 75 mm at RM2.2 | 75 mm, RM2.0 | 75 mm, RM2.1 |
| RM2.4 | 100 mm, RM3.0 | 2 x 50 mm, RM2.6 | 2 x 50 mm, RM2.8 |
| RM3.0 | 100 mm, RM3.0 | Not listed | Not listed |
| RM3.4 | 2 x 63 mm, RM3.6 | Not listed | Not listed |
One caveat first. The target column is the NCC 2019 edition of that selector, published 16 June 2020, so do not treat those targets as current NCC 2025 compliance. What survives the date is the comparison: at the same target the 32 kg/m³ liner is one step thinner than either wrap, and above RM2.4 the wraps must be doubled while Supertel need not be. Section 3.3 also explains Supertel blanket 120954, a 63 mm roll whose title carries no R-value because the current statement lists none at 63 mm. It rates 63 mm at RM1.8, our only source and six years old. R-values here are to AS/NZS 4859.1 at 23°C, air gap excluded.
Where the acoustic numbers exist
An internal liner is usually there for noise as much as heat, and perforated facings let sound through. Bradford publishes acoustic numbers for three of the five, and for one it is a single row.
| Product and facing | Thickness | NRC | Flow resistivity, Rayl/m |
|---|---|---|---|
| Supertel board, plain unfaced | 50, 75, 100 mm | 0.95, 1.05, 1.15 | 17300, 19900, 20100 |
| Supertel board, heavy duty perforated | 25, 40, 50, 75 mm | 0.75, 0.9, 1.0, 1.10 | 24960, 32910, 18100, 44600 |
| Supertel board, Ultraphon | 50, 75 mm | 1.0, 1.0 | 23400, 21600 |
| Supertel board, Acoustituff | 40, 50, 75, 100 mm | 0.8, 0.85, 0.95, 0.9 | Not published |
| Ultratel board, heavy duty perforated | 50, 75 mm | 1.05, 1.10 | 37500 at 50 mm |
| Ultratel board, Acoustituff | 50 mm | 0.85 | Not published |
| Supertel blanket, heavy duty perforated | 100 mm | 1.15 | Not published |
| Flexitel and Multitel blanket | All | Not published | Not published |
Testing was to AS/ISO 354-2006, NRC to ASTM C423-90A, weighted coefficient to AS/ISO 11654-1997, flow resistivity to ASTM C522. Notice what Acoustituff does at the top end: 100 mm drops back to NRC 0.9 while 100 mm plain reaches 1.15. Do not borrow board figures for the blanket, which was tested separately.
Facings, and what Bradford never quantifies
The facing decides whether the product is a vapour layer, an acoustic liner or a tough plant room surface, so it carries more weight in an order than the R-value. The statements use plain, medium duty, heavy duty, heavy duty perforated, and the proprietary Acoustituff and Ultraphon. No Bradford document quantifies any of them: no facing weight in grams per square metre, no tear strength, no perforation open area. All five carry one sentence and stop, that the duty classification does not influence the R-value.
The gap that matters most on a chilled water duct is vapour. Every statement says unfaced glasswool is not a water or vapour barrier, and none gives a permeance for the foil faced versions. The selector goes only as far as saying air and vapour impermeable facings are suitable, with joints lapped and taped. For those joints we stock a 100 mm aluminium and glass cloth tape, code AGFT10050, rated minus 30°C to plus 120°C. Two restrictions catch people out on a coastal plant deck: foil faced product should not touch wet concrete or alkaline materials, and is not suitable within 500 m of saltwater in an unenclosed, ventilated space.
Packs, sheets and the codes that do not line up
Board coverage on our pages is per sheet, not per pack. A variant showing 2.88 m² is one 2400 x 1200 sheet, while Bradford gives the pack: 15311 is 10 pieces and 28.8 m², 15714 is 10 pieces and 36 m², 15371 at 100 mm is 2 pieces and 5.8 m². At 25 mm the two differ by a factor of ten. Blanket variants quote the roll, which matches Bradford.
Not every code we sell is in the current statement. Of the 27 Supertel blanket lines on our page, 14 appear in PTS077. The other 13, including every 1380 and 1390 mm width and a black matt faced R0.7, come from the CSR price catalogue. The board is the same, with our Apex faced sheets at 3000 x 1415 mm and a black matt faced R3.0 absent from PTS075. A submission that cites a document should pick a code it covers, part of specifying insulation for a tender. How much of this a commercial job needs is in commercial versus residential specification.
Four contradictions we have not yet fixed. Our board titles give R2.5 for 88665 and R2.6 for 104210 where Bradford gives R2.2 at 75 mm for both, and 70 mm for 115203 where Bradford gives 67 mm. Code 131884 is a 7.5 m x 1380 mm roll sitting inside a product whose sheets run 2400 x 1200 to 3000 x 1500 mm. And Supertel blanket 40649, titled "Unfaced 1500" on our page, is listed by Bradford under Ultraphon facing. Unfaced is rated to 150°C and faced to 70°C, so treat it as faced until CSR says otherwise. Ultratel needs the same care: our lines name no facing, while Bradford has 77951 perforated, 41906 plain and 15298 in no statement.
The two Multitels
Two Bradford products are called Multitel, and they are opposite on the property most likely to be specified.
| Multitel HVAC Blanket | Multitel BAL 12.5-40 Blanket | |
|---|---|---|
| What it is for | External HVAC duct wrap | Sealing against ember ingress to metal roofs in BAL 12.5 to BAL 40 areas |
| Non-combustible to AS 1530.1 | No, explicitly not classified as non-combustible | Yes, non-combustible when assessed to AS 1530.1 |
| Facing | Plain, medium duty or heavy duty | Unfaced |
| Sizes | 25 to 75 mm thick, 1200 to 1500 mm wide, R0.6 to R2.0 | One size: 25 mm thick, 300 mm wide, 20 m long, code 100061 |
The BAL blanket is not suitable for BAL-FZ or tiled roofs, and is installed to AS 3959 and Bradford's Bushfire Roofing Systems Design Guide. The cross-reference runs one way. The BAL statement says "For the properties of Multitel HVAC Blankets refer to their separate Product Technical Statement", while the HVAC statement never mentions the BAL blanket. Buy the wrong one on the strength of the name and you get a product that fails the requirement it was bought for.
We supply it, and we install batts, wall wrap and sarking
AWBM carries the Bradford HVAC range at Epping. Send us the duct schedule and we will match it to codes, say which the current statement covers, and quote pack quantities rather than per sheet figures. Duct insulation is supply only, and your mechanical contractor installs it. Delivery is $55 in metro Melbourne and metro Sydney, $99 in the outer suburbs and $149 anywhere else in Victoria and New South Wales, set by postcode.
Or browse commercial insulation, acoustic insulation and accessories.
Frequently asked questions
Should HVAC duct insulation be board or blanket?
Board where the surface must hold its own shape: inside rectangular duct, in silencers, on flat plant. Blanket where it has to follow the geometry: round duct, elbows, curved plant, external wrapping. Bradford's rigid options are Supertel and Ultratel HVAC Board, the flexible ones Supertel, Flexitel and Multitel HVAC Blanket.
What is Bradford Supertel?
Supertel is a 32 kg/m³ glasswool in two forms, a rigid HVAC board for internal duct lining and an HVAC blanket. Both run from 25 mm at R0.7 to 100 mm at R3.0, with plain, Acoustituff, heavy duty, heavy duty perforated and Ultraphon facings. Service temperature is 150°C unfaced and 70°C faced.
What is Bradford Flexitel used for?
PTS072 Issue H of May 2026 calls Flexitel a lightweight 24 kg/m³ glasswool blanket for internal or external HVAC rigid duct lining. The 2020 selector's application table put it under external duct wrap only, so the two disagree. We stock 11 rolls from 25 mm at R0.65 to 75 mm at R2.1.
What is the difference between Bradford Multitel HVAC Blanket and Multitel BAL Blanket?
They are different products sharing a name. The HVAC blanket is 18 kg/m³ faced glasswool for external duct wrap, 25 to 75 mm thick, explicitly not classified as non-combustible to AS 1530.1. The BAL 12.5-40 blanket is unfaced glasswool that is non-combustible when assessed to AS 1530.1, in one size only, 25 mm thick, 300 mm wide and 20 m long under code 100061, to seal against ember ingress at metal roofs.
What is the maximum service temperature of Bradford HVAC duct insulation?
All five state the same limits: 150°C unfaced and 70°C faced. Liners and wraps are nearly always faced, so 70°C is the working ceiling. The 2020 selector split faced products into 70°C for paper and plastic based facings and 100°C for glass woven, but the current statements give a flat 70°C.
Do duct insulation blankets absorb sound?
They can, but Bradford only publishes numbers for some. The Supertel blanket has one published result, heavy duty perforated at 100 mm, NRC 1.15, and nothing is published for Flexitel or Multitel. If absorption has to be demonstrated on paper, pick a code with a published figure: the Supertel or Ultratel board, or that Supertel blanket at 100 mm.
What is the difference between Supertel and Ultratel?
Density and application. Supertel board is 32 kg/m³ for internal insulation of HVAC rigid ducts, Ultratel is 48 kg/m³ for silencers and internal duct lining. With a heavy duty perforated facing Ultratel reaches NRC 1.05 at 50 mm and 1.10 at 75 mm, against 1.0 and 1.10 for Supertel. Ultratel also carries higher emissions, VOC 0.5 mg/m²/hr and formaldehyde 0.2 mg/m²/h against 0.15 and 0.03.
Do Bradford glasswool HVAC products comply with AS 1668.1?
No. All five carry the same line: the product does not meet the non-combustibility or fusion temperature requirements of AS 1668.1 clause 2.3.2, and is not classified as non-combustible to AS 1530.1. If the specification cites that clause, no thickness or facing will help, and stone wool is what to look at instead.
Sources
- CSR Bradford, Supertel HVAC Boards, PTS075, Issue I, 13 May 2026. Density, service temperature, the AS 1668.1 and AS 1530.1 limits, fire indices, UL-181 wording, the acoustic table and pack quantities.
- CSR Bradford, Ultratel HVAC Board, PTS082, Issue I, 13 May 2026. Density, application, emissions, acoustic results and codes.
- CSR Bradford, Flexitel HVAC Blanket, PTS072, Issue H, 12 May 2026. Density, application, fire indices and the absence of acoustic data.
- CSR Bradford, Multitel HVAC Blanket, PTS071, Issue G, 1 April 2026. Density, the twelve codes, and no BAL cross-reference. A revision behind its siblings: it cites NCC 2022 and 2019 where the May 2026 statements also cite NCC 2025.
- CSR Bradford, Multitel BAL 12.5-40 Blanket, PTS064, Issue G, 12 May 2026. The BAL product, and the one way cross-reference.
- CSR Bradford, Supertel HVAC Blankets, PTS077, Issue G, 13 May 2026, from the CSR asset library. Density, fire indices, one acoustic result and nineteen codes, fourteen of which we sell. Our blanket page links the board statement instead, and we are repointing it.
- CSR Bradford, HVAC & Industrial Insulation Product Selector, NCC 2016 and 2019 edition, 16 June 2020. Section 3.3, the 63 mm RM1.8 figure, the Flexitel compression wording, facings for dropped codes, the older temperature split and Thermatel at 480°C. Its targets are NCC 2019, and its descriptions and table 4.1 disagree.
- AWBM product catalogue, Shopify Admin API: variant titles, descriptions and custom.datasheet metafields for the five HVAC products, the BAL blanket and tape AGFT10050, which cite the CSR Bradford price catalogue of 28 May 2026. All read 23 September 2026.
General product information, current at September 2026. It does not decide compliance for any building or mechanical system. Whether a duct assembly meets AS 4254.1, AS 4254.2 or AS 1668.1 is for the mechanical consultant and the building surveyor, and the project specification takes priority. Manufacturers revise statements and withdraw sizes, so confirm the current issue with CSR Bradford before ordering.