Building Code Dispute Over Masonry Heaters

Hinges on Masonry Heater Association Cooperation

Report by Walter Moberg

October 21, 1999

At the masonry heater "pow-wow" held in Washington, D.C., last week, key representatives of the two factions of the industry, the manufacturers and the custom heater builders,

(Italics are comments by Norbert Senf)(revised Oct. 23):I disagree with this characterisation. The HPA Manufacturers’ Caucus consists of 3 members, who are all manufacturers. The Masonry Heater Association has 45 voting members, the majority of whom are heater masons. However, there are also at least 14 manufacturers, as well as retailers and others.

met to negotiate a solution to their building code conflict. Both factions desire recognition in the new international building code and, if they can agree on a universal text, stand the probability of support from the Masonry Alliance for Codes and Standards (MACS) in the upcoming meetings with the International Code Council (ICC). If they cannot agree completely, on what is clearly a compromise text, they will no doubt debate each other in front of the ICC committees. This would use up substantial resources from the limited reserves of both factions, and most likely result in both mutual defeat and continued isolation for the industry.

This is a bogus argument. Mr. Moberg is insisting that we "agree completely", or else. We recently spent a full day negotiating and reaching many points of agreement. In fact, only one significant issue remains.

Last year, the Masonry Heater Association (MHA) presented language that was designed only to reflect the construction of the MHA’s version of a custom heater for the IRC Code (International Residential Code — the only one that really matters).

I might add, not only is it MHA’s version, but it is a wide industry consensus with long historical precedent. Implying that it is in any way narrow is misleading.

Unfortunately, this language included restrictions on heater construction designed specifically to exclude some manufactured products.

This is not entirely correct. There is a separate debate in the industry about defining the dividing line between masonry heaters and masonry fireplaces because of clean air regulations. This has been recognized by MHA as not being the purview of the building code, which addresses safety and not emissions. Accordingly, MHA has withdrawn this language.

The manufacturers, specifically the Masonry Heater Manufacturers Caucus (MHMC) of The Hearth Products Association (HPA), were not consulted prior to the submittal.

This language was publicly posted on the Internet, on Jim Buckley's well-known masonry fireplace code site. All MHA members with e-mail at the time were notified - in fact, 2 of the 3 HPA caucus members are also MHA members. In addition, it was posted in the online edition of MHA News, and to a number of listservers, such as Stoves, Chimneys, Greenbuilding, and Strawbale. It was online for several months prior to submittal, with invitations to comment.

They reacted, of course, and when presented with facts, the ICC membership voted to reject the MHA proposal.

The most common opinion on this point, from those who are familiar with the code process, is that the ICC membership wants the industry to "get its act together" before passing anything. However, IBC has already passed.

Now, there is no language in the IRC for masonry heaters, and both factions suffer. The language that passed for the IBC was latched onto a larger submittal by MACS for masonry fireplaces and got in the door on their tailcoat. Without complete industry endorsement, this IBC code section will most likely be removed in the next cycle.

This amounts to a veiled threat. "If you don't give us Carte Blanche on clearances, we will move to have the existing IBC language struck, even though we agree with you on everything else".

If no agreement is reached, the industry (viewed by many from the "outside" world as a bunch of squabbling kids) will not make it out of the sandbox and into the family room.

One of the circumstances that provokes this conflict is the lack of reasonable testing standards for the masonry fireplace and heater industry. UL standards, for example, were written only for metal factory-built and

-assembled appliances and stoves and present severe complications for masonry products. In a recent UL test by one of the heater manufacturers, their product was fired continuously for 12 hours with stacks of dry kindling until the stone approached its melting point and glowed in the dark! (The product survived the test, by the way.) It has been a popular misconception in the MHA that manufacturers don’t need the code, that they can rely on listings for their products.

Incorrect. MHA fully recognizes the inadequacy of UL 1482 as a protocol for masonry heater safety testing.

This, of course, is not true. Conversely, the current codes do not function well for MHA heaters; heater builders are frequently forced to argue similarities with the fireplace code and adjust their construction beyond sensible solutions for efficient heater designs. A new section in the ICC codes is the only possible fair home for both factions to share, at least until reasonable standards can be developed.

Agreed.

So what’s the conflict? The primary remaining issue relates to clearances to combustibles and wall thicknesses, two closely related subjects that are at the heart of all heater construction and installation. Not all Americans want heaters completely exposed in the middle of the room — it is key to successful heater businesses to have the flexibility of near-wall installations.

Obviously. That is not the issue. Assuring fire safety is the issue.

For example, the manufacturers have conceded to allow custom builders 4-inch clearances with 8-inch wall thicknesses, although there is no documentation that this is a safe assumption.

True, as we have freely admitted. However, it is not based on nothing. It is based on existing fireplace code (8" wall) and on ASTM -1604, which was the result of many years of effort by MHA members, and is a true industry consensus document. The 4" (combined, by the way, with a 230F maximum surface temperature limit) is based on "best available experience" and "industry consensus". Test data, obviously, would be better. MHA is currently pursuing this actively, and is planning some initial tests to "ballpark" an overfiring protocol at its test lab this winter. Data will be published as soon as it is available. HPA has indicated an interest in supporting additional third party testing.

(Certainly, it would not be safe if subjected to one manufacturer’s recent UL test!)

This is arguable. The heater in question uses a solid soapstone firebox, which has 600% higher conductivity than other masonry materials. A good argument in favor of code-based prescriptive clearances, based on testing to a peer-reviewed protocol.

In exchange, the manufacturers, whose products are made from a wide range of refractory masonry materials, have proposed limiting their clearances to 4 inches as well,

No one with any masonry heater expertise would argue for less than 4" clearances for solid soapstone heaters. The recent UL specified clearances, referred to above, are 20" rear and 14" sides. Any reductions should be based on an industry consensus testing protocol. MHA has proposed one, and will conduct preliminary testing this winter to move this process forward. Collaboration with the manufacturers’ caucus, and other parties, is welcomed.

but expect to refer to manufacturer’s instructions for wall thicknesses instead of a straight 8-inch wall construction. Many traditional Scandinavian designs, safely installed in tens of thousands of homes, have approved clearances to combustibles that are less than 4 inches with wall thicknesses less than 8 inches.

This point was brought up at the meeting, and was disputed by Rod Zander, who has personal experience in this area.

The MHA position would force manufacturers to change their construction, radically altering proven traditional designs, to fit into their 8-inch minimum specification.

A patently false assertion. MHA has proposed a clear path for including additional products, such as soapstone heaters, and thinner heaters, in the code. The proper arena for this process is the ASTM subcommittee. This is a technical question, not a political question. Rather than spinning our wheels on building code politics and manufacturer self-interest, we should be rolling up our sleeves and doing the necessary work to establish solid clearance standards.

In a recent article, Norbert Senf accused the manufacturers of seeking an "escape clause" and wanting "Carte Blanche" to potentially specify unsafe installations. This is also simply not true.

I stand by that statement. It is a fair and accurate characterization of what this is really all about.

The manufacturers have just as much to lose as the custom heater builders, and there is no greater margin of safety by relying on "skilled and experienced heater builders" than on market-controlled manufactured designs. Proposing to eliminate the manufacturer’s specified clearance is an exclusionary tactic and reverts to the failed approach taken earlier this year.

It is not a question of eliminating the manufacturer’s specified clearance. It is a question of assuring public safety - this is the very purpose of the building code. Anyone who prefabricates a masonry heater is a manufacturer. I count at least 10 small manufacturers among the MHA membership alone. 20+ years of experience in this industry has taught me that even professionals sometimes have creative ideas about the physics of heat transfer that are not necessarily based on reality. It would be extremely unwise to assume that all manufacturers possess the technical expertise to specify safe clearances, particularly without independent review. Fire safety cannot be taken lightly, as it is a life-or-death issue.

I reiterate:

"or, distances specified according to the manufacturer’s instructions"

amounts to Carte Blanche for the manufacturers, with no opportunity for outside review. In my opinion, as experts in the field, we would be negligent in allowing this language.

There must be equal and reasonable access to the code for there to be success for either faction.

The phrase "reasonable access to the code" puzzles me. The code issue here is assuring public safety, not the right to market heaters.

The manufacturers have conceded to allow for restrictions the MHA has sought for size of heaters, channel construction and even to including the words "skilled and experienced heater builders" in the code. Now the MHA must cooperate to allow for manufacturers to continue to build their heaters as they have been reasonably designed.

This sounds like a veiled threat. "Our way, or else".

MHA made as many, or more, language concessions at the meeting as the HPA caucus. Let’s use the agreed upon language and move forward on the safety issue, which is complex.

There is always the possibility of unsafe construction by members of either faction, but a first step must be made that is general and inclusive.

It would be much more than a "first step". It amounts to giving away the store to the marketing interests. It would short-circuit 15 years of progress on safety, and entrench it in the building code.

MHA members have been involved in this process since the beginning with ASTM, with the building code as the ultimate goal. Now that we are getting there, we are being pressured into making unwise, far-reaching decisions by the bogeyman of a Nov. 1 deadline.

Rather than making threats, the HPA caucus should agree to jointly submit the agreed-upon language, and commit to fast-tracking the clearance work that is still required.

There are no "spoilers" here, but without cooperation there will be continued isolation for this still small and, unfortunately, self-limited industry. Hopefully, the membership of the MHA will pull together and direct its representatives to do the right thing — cooperate with manufacturers and end the "war."