"Fire rated batts" is not a product class. In the Bradford Fireseal range it is four products, one per building element: FZ roof batts for a Flame Zone roof edge, party wall batts for inter-tenancy wall joints, a sealer for the head of that wall, and curtain wall batts for the gap at a slab edge. They are not interchangeable, and two are excluded from Flame Zone work.
In short
- Only one of the four is rated for BAL-FZ. The party wall batts and the sealer both say "Not suitable for use in BAL-FZ".
- All three documented products are scoped to Class 1 buildings. An apartment building is Class 2, outside it.
- Density runs 50 kg/m³ for the sealer, 75 for the party wall batts and 100 for the FZ roof batts.
- Bradford publishes no R-value for the FZ roof batt, and nothing beyond size and code for the curtain wall batt.
- Glasswool is non-combustible too, at 0, 0, 0 with smoke developed 1 or below. Heat tolerance splits them: 340 °C maximum service temperature for Pink Batts, 650 °C maximum surface for the FZ batt.
Four products, not one
A spec that says "fire rated batts" was written by someone who knew the building element and did not say so. All four are non-combustible stone wool, so the element is the question.
| What the job or the spec says | The element it is really about | The product |
|---|---|---|
| Fire rated batts, house on a Flame Zone site | Roof edge: fascia, eaves, barge, hip, ridge | Fireseal FZ Roof Batts |
| Bushfire rated roof, BAL 12.5 to BAL 40 | The same edges, lower attack level | Multitel BAL Bushfire Blanket, a glasswool roll |
| Fire batts between two attached dwellings | Vertical joints in the inter-tenancy wall | Fireseal Party Wall Batts |
| Seal the top of that wall | Head of the same wall | Fireseal Party Wall Sealer |
| Pack the perimeter gap | Between a curtain wall and the slab edge, our description only | Fireseal Curtain Wall Batts |
| Fire rated blanket for plant or ducting | Equipment, not a building element | Bradford Fibertex or Fibermesh |
| An FRL such as minus/60/60 on a wall | The whole wall system | None alone. The FRL belongs to the tested system |
That last row catches people out. No Fireseal product carries a fire resistance level: the statements publish material properties and deemed to satisfy clauses, nothing more. Our guide to fire performance in insulation covers why.
The range side by side
Bradford documents each separately, so the four have never appeared together.
| FZ Roof Batts | Party Wall Batts | Curtain Wall Batts | Party Wall Sealer | |
|---|---|---|---|---|
| Thickness | 100 mm | 100 mm | 50 mm | 50 or 75 mm |
| Cut size | 1200 x 115 mm | 1200 x 168 mm | 1200 x 120 mm | 4000 x 300 or 360 mm |
| Pieces per pack | 10 | 5 | 18 | 2 |
| Coverage per pack | 12 lineal m | 1.08 m², 6 lineal m | Not published | 8 lineal m |
| Density | 100 kg/m³ | 75 kg/m³ | Not published | 50 kg/m³ |
| Declared R-value | None published | R2.80 uncompressed | Not published | R1.40 at 50 mm, R2.05 at 75 mm |
| Temperature | Melts 1201 °C, surface max 650 °C | Onset melting above 1200 °C | Not published | Onset melting above 1200 °C |
| Suitable for BAL-FZ | Yes, the only one | No, expressly excluded | Not addressed | No, expressly excluded |
| CSR product code | 125083 | 119161 | 125082 | 123443, 123444, 132796, 132797 |
| Document that covers it | PTS063 Issue C | PTS058 Issue H | None that we hold | PTS059 Issue H |
The empty column is the most useful thing here.
One figure in that table does not add up, and it is worth knowing before you order. CSR prints the party wall batt at 1.08 m² per pack, but five batts cut 1200 by 168 mm come to 1.008 m². The published number is about seven per cent generous, so take the pack count from the length of joint you have to fill rather than from the area.
The roof edge, and the line that splits it
Bradford describes the FZ Roof Batt as insulation for tile and metal roofs, to help prevent embers and flames entering the roof space in BAL-FZ zones, and names where it goes: fascia, eaves, barge, hip, ridge and valley edge areas. It is one component in a system prescribed by AS 3959 Appendix H, and the rest of the build must be to AS 3959.
Twelve lineal metres a pack is the unit a fascia line is measured in. Bradford gives a melting temperature of 1201 °C to ASTM E 794 and a maximum surface temperature of 650 °C to ASTM C 411. We have been loose with the second: our product page says "continuous service to 650 °C", where Bradford says maximum surface temperature to a named test. Use Bradford's wording.
The same roof edge on a BAL 12.5 to 40 site takes a different product. Bradford's Multitel BAL Bushfire Blanket is glasswool, 20 m x 300 mm x 25 mm rolls at 80 lineal metres a pack, capped by its own statement at 150 °C maximum service temperature. Same job, different material, and the BAL rating draws the line.
The party wall pair
Two products serve one wall and they are not alternatives. The batts pack the vertical joints, the sealer runs across the head in one width, and most walls need both.
The R2.80 on the batt, and the sealer's R1.40 and R2.05, carry a footnote that matters more. Bradford states the value is met uncompressed and will not be achieved as compressed packing in a separating wall, where it must be recalculated case by case. Bradford then instructs at least 10 per cent compression for both, so in the installation they are made for, the declared R-values do not apply.
One phrase is the one specifications quote: the product "meets the definition of 'mineral fibre' in the Deemed to Satisfy requirements for Separating Walls". The clause list behind it differs. The batt cites Housing Provisions Standard 2025 at 9.3.1(3)(b) and 9.3.1(4)(b), 2022 Amendment 2 at 9.3.1(4)(b), and NCC 2019 Volume 2 Amendment 1 at 3.7.3.2(d)(ii). The sealer cites the same 2025 pair, 2022 Amendment 2 at both clauses, and NCC 2019 at 3.7.3.2(c)(ii). Quote from the statement for the product you are buying.
The batt with no document
The Fireseal Curtain Wall Batt is 50 mm stone wool cut 1200 x 120 mm, 18 to a pack, CSR code 125082. That is everything a current manufacturer document says about it.
No density, no R-value, no melting or service temperature, no current AS 1530.1 or AS/NZS 1530.3 result, no NCC clause, no evidence of suitability. The PDF linked from the product page is the party wall batts statement, whose codes table lists only 119161. It does not cover 125082, so none of its figures transfer, and we are correcting the link.
The application is ours too: our own data calls it a narrow linear gap in one field and a Class 1 party wall joint in another, and no Bradford statement settles it. CSR Bradford no longer publishes a Product Technical Statement for the batt, and the only sheet we have reached is an archived 2014 one whose smoke developed index does not match the rest of the range. What that document does and does not settle is worked through in curtain wall batts at the slab edge. If an engineer needs a density or a current fire index, we ask CSR.
Class 1 only, and the limits we never published
All three documented products are scoped to Class 1: residential Class 1 for the FZ batt, Class 1 only for the party wall batt, multi residential applications in Class 1 only for the sealer.
Bradford does not define the classes; NCC Part A6 does. Clause A6G2 puts a row house, terrace house, town house or villa unit in Class 1a, each a separate building divided by a fire resisting wall. Clause A6G3 makes a building of two or more sole occupancy units Class 2, where an apartment block sits. "Multi residential" on the sealer document means attached dwellings, and Bradford still ends that sentence "Class 1 Buildings only". Our product page has carried it without the qualifier, reading as though it suits Class 2.
Two limits sit in both party wall documents and on neither of our product pages:
- Not suitable for use in BAL-FZ. The shared name invites the wrong substitution. A builder short on FZ roof batts cannot pack the roof edge with party wall offcuts.
- Does not meet the fusion temperature requirements of AS 1668.1 clause 2.3.2, for ventilation and air conditioning. Neither belongs in fire rated ventilation work.
Two further limits run through all three statements, the FZ batt included: none is for an exposed internal wall or ceiling lining needing a Group number to AS ISO 9705 and AS 5637.1, and unfaced Rockwool is no water or vapour barrier.
One difference is easy to miss: PTS063 Issue C addresses NCC 2022 and 2019, while the two party wall statements address NCC 2025 as well.
Why stone wool rather than glasswool
Stone wool does not burn, but neither does glasswool. Our R3.5 Pink Ceiling Batts data records them as non-combustible to AS/NZS 1530.1, at ignitability 0, spread of flame 0, heat evolved 0 and smoke developed 0 to 1. The Fireseal indices are 0, 0, 0 and 1.
What separates them is the temperature at which the product stops holding its shape.
| Product | Figure | Test |
|---|---|---|
| Pink Batts glasswool | Maximum service temperature 340 °C | ASTM C411/C447 |
| Fireseal FZ stone wool | Maximum surface temperature 650 °C | ASTM C 411 |
A seal works by staying where it was put, which is what those numbers describe. None of it makes stone wool a better ceiling batt: that argument is in insulation materials compared.
Bradford's own fitting notes
The statements carry installation instructions that appear on no supplier page, ours included.
Party wall batts:
- At least 10 per cent compression as a party wall to external wall junction seal, in cavities of 50 mm or less.
- Cut to length accurately and abut adjacent batts, no gaps, when installed vertically.
- To extend a batt, cut an angled or wedge profile on each end for a spliced joint.
- Stagger joints vertically where batts are stacked.
Party wall sealer:
- Install with at least 10 per cent compression.
- Do not route penetrations through the sealer.
- Where an Anticon roofing blanket sits under a metal roof, peel it back so the sealer goes over the foil only.
- Install as a single width across the entire party wall.
The wall detail itself is in insulation in party walls and apartments. All three statements repeat the same caution on cabling: isolate power first, and note the 400 mm limit on wiring to AS/NZS 3000:2018 or later. AS3999 carries further guidance. The blanket instruction belongs to the roofer, not the wall trade.
Coated batts, cavity barriers, industrial blanket
Coated fire batts means a foil faced or mastic coated product, and cavity fire batts is British usage for a tested cavity barrier in a rainscreen facade. We stock neither: every Fireseal item we hold is plain unfaced Rockwool, stated as such in all three statements.
Fire rated blanket for industrial equipment is not a Fireseal query. It belongs to Bradford Fibertex, and to Fibermesh, the same stone wool stitched to a galvanised or stainless steel mesh for pipework and vessels. The grade number is the service temperature, which is the one thing the technical statements do not print, so density is the figure those documents carry: 60, 80, 100 and 110 kg/m³ across Fibertex 350 to 820, and 80 and 100 for Fibermesh 450 and 650. CSR's own product pages carry the temperature sentence, and they give both Fibermesh grades 650 °C, so ask CSR before specifying one. Both sit in the Rockwool collection.
Codes and the order
Quote the CSR product code on any fire order. It removes the ambiguity the word "Fireseal" creates, and the sealer needs one more check. Bradford lists four codes and marks two discontinued as at May 2026: 123443 and 123444, the 50 mm and 75 mm at 4000 x 300 mm. That leaves 132796 and 132797, the 360 mm widths, as the documented current ones. Our own listing carries a third 300 mm option, 494101, which the statement does not cover. Confirm availability before a job depends on a 300 mm width.
The same table marks which codes carry an AS/NZS 1530.3 test report rather than a professional assessment: 123443 and 132796, the 50 mm ones. The indices are identical either way, so it matters only if a certifier asks for the report. 494103 is missing too, so we publish no R-value for either of our own codes.
Where a surveyor has to be satisfied, specifying insulation for a tender covers the documents to collect.
We supply it, and we install batts, wall wrap and sarking
AWBM stocks the Bradford Fireseal range and the rest of the Rockwool line at Epping. Send the element, the building class and the BAL rating, and we will match the product, the pack count and the CSR code, with the manufacturer statement before you commit. 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 fire protection, Rockwool and wall insulation.
Frequently asked questions
What are fire rated insulation batts?
Four non-combustible stone wool products in the Bradford Fireseal range, one per building element: FZ roof batts for a Flame Zone roof edge, party wall batts for inter-tenancy wall joints, a sealer for the head of that wall, and curtain wall batts for a slab edge gap. Only the FZ batt is rated for BAL-FZ. Pick by element, then quote the CSR code.
What is the difference between Fireseal party wall batts and the party wall sealer?
The batts are 100 mm at 75 kg/m³, cut 1200 x 168 mm, five to a pack, and pack the vertical joints. The sealer is 50 kg/m³ in 4000 mm lengths, 50 or 75 mm thick, and goes on as a single width across the whole wall.
Can Fireseal party wall batts be used in a BAL Flame Zone roof?
No. Both party wall documents carry the line "Not suitable for use in BAL-FZ". The only Fireseal product rated for Flame Zone is the FZ Roof Batt, code 125083, and even that is one component in a system prescribed by AS 3959 Appendix H.
What is the R-value of Bradford Fireseal batts?
The party wall batt is R2.80 uncompressed, the sealer R1.40 at 50 mm or R2.05 at 75 mm. Bradford publishes none for the FZ roof batt or the curtain wall batt, and says neither value is achieved as compressed packing in a separating wall, which is the job.
Are Fireseal products suitable for a Class 2 apartment building?
No. All three technical statements say Class 1 buildings only. NCC clause A6G3 makes a building of two or more sole occupancy units Class 2, where an apartment block sits, so the documented scope does not reach it. Take a Class 2 job to the fire engineer.
What are fire rated mineral fibre batts?
It is the wording a specification uses when it wants a product meeting the deemed to satisfy definition of "mineral fibre" for separating walls. Bradford's party wall batt statement says exactly that, at Housing Provisions Standard 2025 clauses 9.3.1(3)(b) and 9.3.1(4)(b). The sealer uses the same phrase on a different clause list, so quote from the document for the product you order.
Do you sell coated fire batts or cavity fire batts?
No to both. Every Fireseal product we stock is plain unfaced Rockwool, so there is no foil faced or coated option. Cavity fire batts in the British sense means a tested cavity barrier for a rainscreen facade, and nothing we carry is documented as one.
Where can I buy fire batts in Victoria or New South Wales?
AWBM stocks the Bradford Fireseal range at Epping and delivers across Victoria and New South Wales: $55 in metro Melbourne and metro Sydney, $99 in the outer suburbs and $149 beyond that, set by postcode. Send the building element and the code if you have one.
Sources
- CSR Bradford, Fireseal FZ Roof Batts, Product Technical Statement PTS063 Issue C. Everything here about the FZ batt.
- CSR Bradford, Rockwool Fireseal Party Wall Batts, Product Technical Statement PTS058 Issue H. The party wall batt, including its fitting notes.
- CSR Bradford, Rockwool Fireseal Party Wall Sealer, Product Technical Statement PTS059 Issue H. The sealer, including the May 2026 discontinuation note.
- None of those three prints a publication date, only an issue letter. Our copies entered the AWBM library on 12 August 2026.
- CSR Bradford price catalogue, 28 May 2026, via our own catalogue. Curtain Wall Batts code 125082 and Multitel BAL Bushfire Blanket code 100061.
- Fletcher Insulation technical data sheet for Pink Batts Ceiling, RTDS9 Revision 7, 17 February 2025, as cited in our product data. The 340 °C figure and the glasswool fire results.
- CSR Bradford PTS069 Issue D (Fibermesh 450 and 650) and the Fibertex 350 Issue B, 450 Issue C, 650 Issue G and 820 Issue J statements. The densities, and the absence of a published service temperature.
- CSR Bradford product pages for the four Fibertex grades and Fibermesh, read 23 September 2026. The service temperature sentence the technical statements leave out, and the 650 °C given to both Fibermesh grades.
- CSR Bradford, Multitel BAL 12.5-40 Blanket, PTS064 Issue G. The roll size, lineal metres a pack and the 150 °C limit.
- NCC 2022 Volume One, Part A6 Building Classification, clauses A6G2 and A6G3 at ncc.abcb.gov.au, read 23 September 2026. The Class 1a and Class 2 definitions.
- Standards and NCC provisions are otherwise quoted as cited inside the Bradford statements, not from the standards themselves.
Product selection information, current at September 2026. It does not decide compliance for a building. A fire resistance level, a Group number and a BAL assessment belong to the design and the tested system, so the fire engineer and the surveyor come first. Manufacturers change specifications and withdraw codes, so check the current statement before you order.