“Don’t Get Collared!”

Introduction:

Some alternative solutions/fire safety engineering designs that are using the performance requirements of the Building Code of Australia are omitting the otherwise deemed to satisfy fire collars in so-called “wet areas”, and allowing the use of plain plastic pipe penetrations (without a fire collar) but with only an additional smoke seal. The author has been asked to review the overall cost savings (product and labour), that may or may not result from this specific alternative solution, as it has been discussed by fire collar manufacturers, plumbing suppliers and plumbing contractors, that in fact there may not be any significant cost-saving and that the Fire Safety Engineers are in fact reducing the overall safety of buildings, with no significant cost savings to the Developer.

Typical penetration requirement for a residential apartment

Of course, not all high rise residential apartments are the same in terms of fixtures and fittings. They do vary in relation to the plastic pipe penetrations that would extend beyond the fire-rated floors and/or walls.

A typical apartment might include the following:

Floor penetrations (cast in type collars)

  • Bathroom toilet /pan ø100mm
  • Bathroom floor waste ø80mm or ø100mm
  • Bathroom basin ø50mm
  • Bathroom shower ø50mm
  • Laundry floor waste ø80mm or ø100mm
  • Laundry sink / trough ø50mm
  • Laundry washing machine ø50mm

Total floor penetrations

3 x ø100mm & 4 x ø50mm (7 collars in total)

Wall penetrations (wall type collars)

  • Main waste (to riser shaft) ø100mm
  • Vent (to riser shaft) ø50mm

Total wall penetrations

1 x ø100mm & 1 x ø50mm (2 collars in total)

Basis for comparisons

The majority of the fire collar requirements under BCA deemed to satisfy provisions are the floor penetrations, which for the typical apartment specified above, relates to 7 fire collars. This analysis will therefore focus on the floor penetrations only.

Installation requirements

(floor penetrations)

The most cost-effective method of preparing a floor slab to accommodate a plastic pipe penetration, it to use some type of “mould” or “plug” that is attached to the formwork, and after the concrete is poured, it is removed or in some

cases stay in situ and leave behind a void or core hole to accommodate the proposed plastic pipe penetration.

This “or “mould” or “plug” is commonly referred to as:

  • For fire rated application – a cast in type fire collar (incorporating intumescent material)
  • For non-rated application a non- rated collar

The use of cast in collars, is method typically used for all high rise residential apartments type projects.

The alternative method is drilling a core hole after the slab has been poured and has cured, which is both expensive, time consuming and involves another specialist trade.

Cast in collars (core hole) devices

There a three (3) collar alternatives commonly used by plumbers to make the cast in type core holes:

  1. Plain non fire rated collar (with cap) but without any integral smoke seal, e.g. Promat Pipeseal®
  2. Non fire rated mould or plug (with cap) and with integral so called smoke seal,

e.g. Keyplastics Keyseal®

  • Conventional proprietary fire rated, intumescent fire collars – cast in type,

e.g. Promat Promaseal ® Cast-in PolyCollar, Pyropanel Cast-in collars, Hilti CP680 Cast-in firestop collar, Tyco cast-in collar (with or without integral smoke seal).

Any of these product that are cost effective, will be manufactured from plastic and will be left in situ inside the slab after the form work is removed.

Traditionally, these devices were made from steel to provide a robust device, as form-working trades are typically very rough and demand a robust design.

Recent advances in plastic technology and proprietary product innovations has seen the introduction of the use of plastic for the bodies of both the non-rated collars and fire-rated collars for this application. This has had a significant impact on a reduction in their manufacturing and selling costs.

Cost comparisons for three (3) alternatives

General

Material costs: Costs for materials are based on selling prices and using major project pricing from major plumbing wholesales to plumbers at the time of writing.

Labour costs: The labour costs to fix the unit to the formwork and subsequently remove the cap and insert the pipe is identical in all three cases, so for comparison purposes can be ignored.

Material costs: Costs for materials are based on selling prices and using major project pricing from major plumbing wholesales to plumbers at the time of writing.

Labour costs: The labour costs to fix the unit to the formwork and subsequently remove the cap and insert the pipe is identical in all three cases, so for comparison purposes can be ignored.

Material costs: Costs for materials are based on selling prices and using major project pricing from major plumbing wholesales to plumbers at the time of writing.

Labour costs: The labour costs to fix the unit to the formwork and subsequently remove the cap and insert the pipe is identical in all three cases, so for comparison purposes can be ignored. Additional labour costs apply only to System 1 for the system without an integral seal.

Note : The best efforts have been taken to get accurate costs at the time of writing and the author is confident that the costs accurately reflect the real situation at present.

The fact that a collar (“mould” or “plug”), is necessary to make the void or core hole in the cast in type situations, whether it is to be fire-rated or not, is I believe a key item overlooked by the developer and some fire safety engineers. In the author’s opinion, this oversight perhaps results in a perceived, but not really cost saving and an attraction to omit fire collars and use an alternative solution allowing a plain plastic pipe penetration with an additional smoke seal only.

Relative cost comparisons

Fire collar versus alternative solution incorporating separate smoke seal

From the analysis above, the alternative solution (System 1), which is the most common alternative solution proposed is in fact MORE EXPENSIVE by $3.50 per collar omitted than using a “conventional” deemed to satisfy fire rated collar (System 2).

So for a high-rise apartment, say with 40 storeys and 10 apartments per storey, and 7 collars per unit, for this scenario, this accounts to total additional cost of $9,800.

Fire collar versus non-rated collar with integral smoke seal

From the analysis shown above, the relative cost saving for omitting a fire collar is in the order of ONLY $0.50 per collar omitted (floor penetrations only – which are the majority of the penetrations as discussed above).

So for a high-rise apartment, say with 40 storeys and 10 apartments per storey, and 7 collars per unit, for this scenario, this accounts to a total project cost saving of $1,400.

Discussions with hydraulic consultants and plumbing contractors

Some interesting observations and quotes came from discussion with some key hydraulic consultants and plumbing contractors

  • “Don’t fire engineers realize that we still need a non-rated collar (“mould’ or “plug”) anyway to produce a core hole during the concrete pour and that this item is effectively the same price as a conventional fire collar”
  • “The alternative solution requesting a smoke seal is not practical and the smoke seal is often not installed correctly or at all, is hard to verify, and often its applicability to the original scope of works quoted is debated  and charged as an “extra” to the builder / developer”
  • “We have been using fire collars and removing the intumescent”, as these are more readily available and we get volume purchase discounts.
  • “Don’t fire engineers realize that we still need a non-rated collar (“mould’ or “plug”) anyway to produce a core hole during the concrete pour and that this item is effectively the same price as a conventional fire collar”
  • “The alternative solution requesting a smoke seal is not practical and the smoke seal is often not installed correctly or at all, is hard to verify, and often its applicability to the original scope of works quoted is debated and charged as an “extra” to the builder / developer”
  • “We have been using fire collars and removing the intumescent”, as these are more readily available and we get volume purchase discounts.

Technical issues for smoke seals ( authors views)

A smoke seal, if incorporated into an alternative solution, should have some proven performance for the application in question. It should have been tested to the principles of AS/NZS1530/7 system, and should be specified based on a maximum leakage rate in m3/hr, at a given pressure differential, after exposure to medium temperature smoke (200 deg C) after 30 minutes exposure. This will ensure the smoke seal, which might be a silicone or intumescent sealant, will in fact stay in place and not fall out due to shrinkage or the effect of the medium temperature (warm) smoke.

Identification issues

For the alternative solution it is difficult to inspect and verify if the installation is in accordance with the requirements. For a conventional fire collar, they can be visually inspected.

For the option where the additional smoke seal is by way of a sealant, it is more difficult to ensure the correct application annular space and depth of sealant applied, and to verify that the correct product has been used.

For the option where a non fire rated cast- in type collar is used, some contractors are asking the conventional fire collar manufacturers to produce a co called “smoke collar”. These may be simply conventional fire (and smoke) collars, without the intumescent, whereby they are the same colour and same dimensions.

How does the inspector determine, particularly where some penetrations need to be fire rated and some only smoke rated (the alternative solution penetrations), which ones are the fire collars and which ones are the smoke collars?

Conclusions

In the case of omitting fire collars by way of alternative solutions, it is the author’s views that the cost saving are minimal and DO NOT adequately compensate for the additional risk.

The additional risk that will be shared jointly by the developer, fire safety and relevant building surveyor, could easily be avoided by installing fire collars and relying on the “safety blanket” afforded with BCA deemed to satisfy provisions.

The author has sympathy for developers, fire safety engineers and relevant building surveyors as they have too many issues to deal with, and the pace at which building developments are progressing, and the conflicting day to day commitments, make it difficult to properly research issues like this specific one.

The manufacturers of Passive Fire Protection products have identified this shortcoming in key participants understanding of true costs for their products, and are happy to provide similar reports for other products or systems as required through the services of the author.

In short, the author’s view is “DON”T GET COLLARED – USE FIRE COLLARS FOR YOUR PROJECTS – THERE IS NO APPRECIABLE COST SAVINGS.

Disclaimer

This report has been prepared in good faith and the author takes no responsibility for any errors omissions that may cause damages to third parties. Appendices have been taken from supplier web sites and from promotional literature at the time of writing.

Appendices

Appendix 1 – Keyplastics Keyseal ® – non rated cast in collar

Appendix 2 – Promat Promaseal ® – Cast-in fire collar

Appendix 3 – Tyco Tower Cast-in fire collar

Appendix 4 – Pyropanel Pyrosleeve ® Cast-in fire collar

Appendix 5 – Hilti CP680 Cast-in firestop collar

Note – Appendices are not included in this abridged version – contact author for more information