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Consumer protection advisories issued by Government
departments
Advisory:
April 11th, 2013 - The Minnesota Department of Commerce
(NEW)
Advisory: January 31st, 2013 - U.S. Federal Trade Commission
(NEW)
Advisory: June 8th, 2010 - U.S. Federal Trade Commission
Advisory: March 5th, 2009- U.S. Federal Trade Commission
Advisory: February 01, 2009 - State of Nebraska
Evaluation
Advisory: September 26th, 2008
- State of Wisconsin Evaluation
Advisory: October 5th, 2006 - U.S. Federal Trade Commission
Advisory: April 3rd, 2002 - U.S. Federal Trade Commission
Advisory: January 31st, 1992 - U.S. Federal Trade Commission
For the building inspectors and designers
Pay Now or PAY Later
All Points Bulletin
Additional reading
Advice to consumers
Should you insulate under slabs?
How much should you insulate under a slab?
Research & Science vs. S & M (Smoke & Mirrors from Sales &
Marketing)
Since 1979 I've seen building products come and go and none has been as entertaining as the ebb and
flow of insulating products particularly the reappearance of what I call reflective
bubble 'faux' insulation or snake oil foil for under slab radiant applications. This
is a classic case of marketing masquerading as science and solutions looking for problems where none exist.
According to the government run Consumer Sentinel protection services, Shop at Home/Catalogue Sales is one of the highest ranked frauds in North America so if you are considering purchasing reflective bubble "faux" insulation
for underslab applications or any application in cold
climates - either online or at a distribution outlet -
with all due respect to Shakespeare, remember these words -
double bubble with foil is trouble...
Read these excerpts and links from around the world...and make
note of how long this has been going on - starting with
1989:
Barriers to
radiant barriers, Home Energy Journal, 1989
"They have been the subject of much controversy, as the
claims made by many manufacturers were extreme (up to 100%
heat shielding), with the consumer paying high prices for
ineffective devices."
NRC-IRC, Institute for Research in
Construction
, 1991
"...multiple reflective materials do not address conduction and convection losses in building envelope cavities well enough to warrant their use in colder climates...The reduction in heat loss suggested by the product literature, however, was not achieved...In terms of
cost, reflective materials are subject to the same principles of diminishing returns as conventional insulation. If it is not cost-effective to add more conventional insulation, it is probably not cost-effective to add a
radiant barrier."
Federal
Trade Commission: Manufacturer of home insulation charged
with
violating r-value rule; will pay civil penalty to settle
complaint, 1992
"the
defendants manufactured, distributed, sold and promoted "Perma
R Plus" home insulation with R-values that were not based on
R-value tests conducted according to the test procedures
required by the rule."
The North American Insulation Manufacturers Association, 1999
"In determining the R-value of reflective insulation, NAIMA believes evidence supports that the detrimental impact of dusting and corrosion frame the evaluation of thermal performance. The Department of Energy’s ("DOE") "Radiant Barrier Attic Fact Sheet," issued in June 1991, reported
laboratory measurements verifying that dust on the surface of aluminum foil increases the emissivity and decreases the reflectivity. Based on this finding, the DOE concluded that "dust or other particles on the exposed surface of a
radiant barrier will reduce its effectiveness.’ Thus,
observed the DOE, reflective insulation installed in locations that collect "dust or other surface contaminant will have a decreasing benefit to the homeowner over time." For instance, when DOE monitored reflective insulation installed in a dusty attic, researchers observed that 50 percent
of the insulation’s effectiveness dissipated after the first year of installation"
Canadian Construction Materials Centre Evaluates Thermal Resistance of Low Emissivity Sheet Material, 1999
"When the
low emissivity sheet material
is installed in the wall system...the effective R-value of this material in combination with the air spaces and the strapping material (furring) used to create the air spaces will account for about 26% of the thermal resistance of the wall, whereas
the low emissivity material itself will account for only about 5%. (The RSI value of the material is in the order of 0.18.)
Louisiana Department of
Natural Resources, Insulation Comparison Demonstration, Funded By U.S. Department of Energy, 1999
"Our comparison tracked the amount of energy required to maintain the interior temperature of the three buildings at a constant 72 degrees F. In this demonstration mass insulation, using fiberglass, required less energy to maintain the set point temperature, for all four seasons, than did
either the radiant barrier building...The
radiant barrier building required more energy than the fiberglass building...to maintain the set point temperature for all four seasons. In this specific comparison, the fiberglass insulated building performed the best out of the three buildings."
Building
Standards Saskatchewan Municipal Affairs, Building Officials
Newsletter, 2001
"Clearly, the result of misusing the listings, despite a
builder’s good intentions, could leave a building owner with
a product that has not been demonstrated to perform as
required, and could leave a building official with having to
explain why use of the material (reflective
foil insulation) in this application was
approved."
ASHRAE Fundamentals Handbook, 2001
"Values for foil insulation products supplied by manufacturers must also be used with caution because they apply only to systems that are identical to the configuration in which the product was tested. In addition, surface oxidation, dust accumulation, condensation, and other factors that
change the condition of the low-emittance surface can reduce the thermal effectiveness of these insulation systems (Hooper and Moroz 1952). Deterioration results from contact with several types of solutions, either acidic or basic (e.g., wet cement mortar or the preservatives found in
decay-resistant lumber)."
The North American Insulation Manufacturers Association, 2001
"...one can only conclude that the
reflective bubble pack products do not meet the International Mechanical Code (IMC). Since all other model codes incorporate similar if not more stringent requirements, it is unlikely that the reflective bubble pack insulations meet any of the model
mechanical codes."
Florida Solar Energy Center, 2001
"...horizontal application...the later will significantly
degrade in performance from eventual
dust accumulation (Fairey
and Beal, 1988; Levins et al., 1990)."
Aluminium Foil Insulation Association: Beware
of unsubstantiated r-value claims, 2002
"It
has recently been brought to AFIA’s attention that some
insulation companies operating in Queensland, may be
promoting
unsubstantiated total in-service computation R-Values
that have not been subjected to independent assessment and
have not been calculated in accordance with current
Australian and International Standards."
Energy Fact Sheet -
Radiant Barriers, Southface Energy Institute, 2002
"Many do not feel the modest winter savings are worth the
risk of moisture problems or the likelihood of dust
accumulation, which could eliminate any savings."
Energy Design Update, November 2003
(A Note on the 2003 Energy Design Update article: You will need a subscription to obtain the complete text wherein several
bubble foil
firms made these apologies), "…apologies to anyone confused by the statement”, “This was an oversight on our part”, “we realized it was erroneous” ,
“apologize for the misconstrued quote”. (To RIMAs credit they are doing their best to curb this behavior but many other unscrupulous firms continue to sell the snake oil foil story for under slab applications to
unsuspecting consumers).
Federal Trade Commission Requirements, 2003
"The R-value Rule specifies substantiation and disclosure requirements for
thermal insulation
products used in the residential market, and prohibits certain claims unless they are true.
CMHC Comparison of
Under Floor Insulation Systems, 2004
"The bubble-pack insulation had a low insulating value compared to the polyurethane panels and the XPS board. It’s cost benefit was the poorest of all insulating materials tested."
Plumbing & HVAC Product News, 2004
“The floor we tested with
bubble foil underneath did not look like it had any insulation underneath,” reported senior researcher in the CMHC policy and research division.
Federal Trade Commission Advisory Letter, 2004
"The FTC staff is aware of claims that are being made in the marketplace for foil-faced bubble pack products (or similar
reflective or radiant barrier products) installed under concrete slabs. In the staff's view, it may be misleading for industry members to suggest that such foil
products will reflect radiant heat when installed under concrete."
U.S. Department of Energy, 2004
"In heating dominated climates, they (radiant barriers) aren't very economical nor recommended in most cases. Unlike other insulation, there currently isn't a standard method for equating
how well a radiant barrier works. Many
manufacturers use the term "equivalent R-value." This really has no scientific meaning, and it often reflects optimum conditions and not necessarily climate conditions."
Bad Science, By John Siegenthaler, P.E., 2005
"Imagine a new insulation material with a claimed R-value almost six times greater than standard extruded polystyrene. So high, in fact, that no other established insulation product even comes close to offering the same R-value/thickness combination. When installed below a
heated slab, this material makes downward heat losses almost nonexistent. How is such spectacular
thermal performance achieved? What have all those scientists at Dow, CertainTeed, Owens Corning and the other insulation giants been missing all these years?"
Building America Best Practices Series: Volume 3 –
Builders and Buyers Handbook for Improving New Home
Efficiency, Comfort, and Durability in the Cold and Very
Cold Climates, US Department of Energy, Pacific Northwest
National Laboratory and Oak Ridge National Laboratory, 2005
"Reflective Insulation Systems -
Reflective insulation systems
are fabricated from aluminum foils with a variety of
backings such as roof sheathing, craft paper, plastic film,
polyethylene bubbles, or cardboard. These systems are not
recommended for the cold and very cold climates. If a single
reflective surface is used alone and faces an open space,
such as an attic, it is called a radiant barrier. Radiant
barriers are not recommended for cold and very cold
climates."
The Insulation Council of Australia & New Zealand,
2005
"It appears from the test results that a significant number
of manufacturers and suppliers of insulation products are
not meeting the required standards under the BCA...thermal
performance cannot be left in the hands of manufacturers
(and their trade associations) and must be endorsed by a recognised testing laboratory as per the standard."
Florida Solar Energy Center, 2005
"As in most cases, claims for radiant barriers that sound
too good to be true are too good to be true. If your roof
accounts for less than 20 percent of your cooling load, then
an attic radiant barrier can't possibly save more than 20
percent on your bills...over time,
dust may accumulate on
the surface of foil facing up. The dust will reduce the
radiant barrier effect by allowing the foil to absorb rather
than reflect thermal radiation."
Heating, Refrigeration, Air Conditioning Institute of Canada Advisory Letter
In direct reference to
bubble foil insulation, "Selecting materials that do not meet the minimum code requirements can significant affect comfort for the consumer through excessive wasted heat into the ground and could be a very expensive proposition to rectify the condition."
A study of energy efficient measures for
Part 9 Housing in the Ontario Building Code, 2006
“Reflective
surfaces of insulating materials shall not be considered
in calculating the thermal resistance over building
assemblies.”, A study of energy efficient measures for Part
9 Housing in the Ontario Building Code, for the Ontario
Ministry of Municipal Affairs and Housing, Report by Lio and
Associates, June 2006
FTC Stops Allegedly False Claims About Insulation Performance
, 2006
"The
FTC complaint alleged that advertising claims for “The Barrier” exaggerated its R-value by over 600 percent compared to test results and misrepresented other
thermal performance characteristics of the insulation. The FTC also charged that labeling for “The Barrier” and Microfoil insulation did not mention the products’ R-values or explain the meaning of R-value, as required by law. The complaint also alleged other violations of the R-value Rule, including the publication of ads comparing “The Barrier” to competing products without disclosing the R-value
for both products."
Multi-foil insulation products Compliance with Reg.7 and Req. L1, 2006
"In other words,
multi-foil manufacturers who have used the comparative testing route are claiming the insulating properties of their product to be approximately three times better than can be verified using existing National or European test standards."
SUSTAINABLE SOLUTIONS for BUILDINGS, 2006
"Testing undertaken by the National Physical Laboratory (NPL) appears to show that a
multi-foil insulation product, when tested in a hot box against the internationally accepted standard for thermal insulation, does not meet claimed insulation values...when tested in accordance with BS EN
ISO 8990:1996."
NHBC Guidance on Multi Foil Insulation, 2006
"The NHBC has recently published guidance regarding multi-foil insulation performance in its Standards Extra, to the effect that multi-foils will not be accepted under its warranty arrangements until a consensus on the performance and testing of these materials is achieved."
TIMSA welcomes clarification of insulation regulations, 2006
"This guidance resolves a growing problem whereby claims for thermal resistance of
multi-foil materials based on arbitrary testing indicated much higher values than have been obtained when these materials are subjected to proven, relevant standard test procedures – sometimes by a factor of
five...over recent years many buildings have been completed with foil materials not certified by accredited bodies which may not even satisfy the standards required by Part L: 2002, putting seriously at risk the Government’s stated intention to raise buildings’ energy performance
standards..."
Energy Design Update , September 2006
"...the statement is kind of deceptive, because it gives the impression that if you use this product
(reflective
insulation), you will cut the heat flow through the wall by two-thirds, and that clearly isn’t true."
Wisconsin Department of Commerce, 2006
"...the state of Wisconsin does not recognize the
reflective
foil facing used on the product...“P2000” reflective
insulation board will only be allotted an R-5 per inch..."
Energy Design Update , September 2006
"...the marketers of
P2000* have made claims about R-value performance that are much higher than those in C-578 and are rightly being challenged to prove it."
Wisconsin Department of Commerce, 2006
"...this product can be installed but no credit will be
given as
under-slab insulation...SHALL NOT BE INSTALLED AS A
STAND ALONE PRODUCT IN LIEU OF THE CURRENT CODE
REQUIREMENTS."
Radiant Panel Association Newsletter, 2007
"Reflective foil under a slab, with no airspace, is totally ineffective as an insulator.
Reflective foil with a bubble or foam core is only slightly more effective than the bubble or foam by itself."
The UK Mineral Wool Association, 2007
"In recent months the government has moved to give guidance on the use of
multi-foil insulation...It has written to all local building control departments and to bodies such as the NHBC...(advising) they could no longer accept the thermal values claimed for (brand x) and similar products"
Sustainability Magazine, 2007
"The architects who specify such products and the building engineers who sign off houses insulated with them may be leaving themselves open to
litigation from clients who will understandably be very angry that their new home is not insulated to the required standard."
Northwest Energy Efficiency Alliance and
Washington State University Extension Energy Program,
Product & Technology Reviews, 2007
"We found no basis for the manufacturer’s
claim of 77% reduction in heat loss due to (brand X) in an
under-slab application. This heat loss reduction
significantly exceeds even that of 2” extruded polystyrene
insulation installed under the full slab, while the
insulating value of (brand X) is much less...We conclude that an
under-slab installation is not a good application for this
type of product (bubble foil), even if only used to replace a vapor
retarder."
This is an excerpt from an advisory from Natural Resources Canada, Released May
2007:
"As a result of countless inquiries from the general public, building contractors and building professionals concerning claims made by manufacturers of foil-faced bubble insulation (FFBI) products, Natural Resources Canada (NRCan) has prepared this paper dealing with the effective thermal
resistance (RSI/R value) of these and other reflective types of products for the purpose of energy modeling under its energy efficiency housing initiatives."
Read the
full NRCan text on bubble foil.
This is an excerpt from Thermal Insulation Manufacturers and Suppliers Association, Statement on Multi-foils, Released May
2007:
"...some multi-foil producers have been claiming thermal resistances or U-values based upon unproven, and therefore non-approved, comparative field test methods. These non-approved methods give apparent thermal values significantly better than those obtained using the Hot Box method. TIMSA
does not accept thermal resistance values or U-values based on such methods and advises that such values should not be accepted for any project under current Building Regulations: Part L- 2006."
Reflective Insulation Manufacturers Association, 2008
"Claims of high R-values for
reflective products
when they
are used as under concrete insulation are not supported by
any industry or code body accepted testing methods. Products
installed under concrete slabs cannot reflect heat because
there are no air spaces present."
Forest of Dean, District Council, Building Control Newsletter,
2008
"Q. Can I use a multi-foil insulation alone?
A. The latest guidance dated April 2008 that we have been
informed about from the Local Authority Building Control
(LABC) is as follows: The group remain of the opinion that
the thermal performance of all insulation materials should
be determined by testing to National and European standards
by organisations who are accredited to do so. On this basis
there are currently no
multi-foil products that can reach
the current Building Regulation standard when used alone as
a single layer."
The Environmentally Responsible Construction and Renovation
Handbook, Public Works and Government Services Canada, 2008
"If
radiant heating sources are embedded in floors-on-ground
or in walls, the assembly must be insulated to a level 20%
better than the maximum overall U-value allowed by the MNECB
tables".
Natural Resources Canada's (NRCan's)
validation of new building designs policies and procedures
and interpretation of the Model National Energy Code for
Commercial Buildings (MNECB),
2009
Foil Back Bubble Wrap as insulation (Clarification of
MNECB 3.2.3.3)
"Question: Will using only foil back bubble wrap for
insulation under my radiant slab meet the Model National
Energy Code for Commercial Buildings (MNECB) requirement
3.2.3.3 for Natural Resources Canada's (NRCan’s) validation
service?
Answer: No, using only
foil back bubble wrap will not
meet the MNECB mandatory requirements. A study by the
Canadian Mortgage and Housing Corporation (Technical Series
04-127) shows a double-layer bubble wrap with an
intermediate foil layer with an equivalent RSI value of only
0.4.
You should note that NRCan’s validation of new building
designs will only recognize results from third-party testing
for products or materials from organizations such as the
Canadian Standards Association and the American Society for
Testing and Materials. "
Natural Resources Canada's (NRCan's)
validation of new building designs policies and procedures
and interpretation of the Model National Energy Code for
Commercial Buildings (MNECB),
2009
Under Slab Insulation with Radiant
Floor Heating (Clarification of
MNECB 3.2.3.3-3)
"Question:
If a portion of the slab contains
radiant floor heating, must I
insulate under my entire slab
according to the Model National
Energy Code for Buildings (MNECB)
requirement 3.2.3.3-3 for Natural
Resources Canada's (NRCan’s)
validation service?
Answer:
To qualify for
NRCan’s validation of new
building designs and to meet the
interpretation of
MNECB 3.2.3.3-3, you must
insulate slabs with imbedded heating
ducts, cables or pipes under their
full area in which radiant heat is
installed as per Table A-3.2.3.1 of
Appendix A. Areas of the slab
without installed heating ducts,
cables or pipes need only comply
with the other requirements of
MNECB 3.2.3.3.
You
must physically isolate the sections
of the slab on grade with installed
heating ducts, cables or pipes from
the unheated parts of the slab,
either by vertical insulation or by
an expansion joint. Or the under
slab horizontal insulation below the
heated sections must extend beyond
the edges of the area being
radiantly heated to a distance of
four times the thickness of the
slab."
State of Nebraska, 2009
"Although the p2000 marketing materials do provide reference
to some ASTM tests being completed – the completed tests
are not the appropriate tests required
under the
R-values
regulations of the Federal Trade Commission regulations."
* P2000 is an EPS insulation manufactured by Polar Industries.
Autodesk / Ecotect, 2009
"...foil by itself does not provide
thermal resistance; foil facing an air space increases the
resistance of the air space. The increase in resistance
achieved by subdividing will be reduced if any air is
allowed to move from one space to another or if the
reflective surface becomes coated with dirt or
condensation."
Federal Trade Commission - Courts Bar
Firms from Making Deceptive Claims for Home Insulation
Products, 2009:
Sellers
Greatly Exaggerated Their Products’ Effectiveness
"The FTC today announced three R-value Rule enforcement
actions – a stipulated final order settling charges against
Enviromate, LLC, and its principal, Phillip A. Geddes; and a
second order against Meyer Enterprises, LLC, Insulated
Solutions, LLC, and Donald L. Meyer; as well as a federal
district court complaint against Edward Sumpolec, doing
business as Thermalkool, Thermalcool, and Energy
Conservation Specialists."
Craven, C., Garber-Slaght, R.,
Reflective Insulation in Cold Climates, Technical Report
Number TR 2011-01, Cold Climate Housing Research Center,
Alaska, April 2011
"Simply put, the contribution of
reflective insulation to the building envelope in cold
climate construction is minimal, especially when viewed in
the context of the total R-value of the building envelope."
Dick, K., Fedirchuk, K., Comparison
of Energy Consumption for a Wood Frame Building using Batt
insulation and a Foil Backed EPS Foam Board, University
of Manitoba, 13th Canadian Conference on Building Science
and Technology, Winnipeg, May 10-13, 2011
"Based on this test Foil-Backed FB-EPS required about twice
the energy to maintain a set-point temperature as did
fibreglass batt insulation...FB-EPS was not able to maintain
set-point temperature during a portion of time."
Straube, J., Lstiburek, J., Pettit, B., Rudd,
A., Schumacher, C., Baker, P., Ueno, K., Lukachko, A., Smegal,
J., Grin, A., Neuhauser, K., Gates, C., Building
America Special Research Project: High R-Value Enclosures for
High Performance Residential Buildings in All Climate Zones
Research Report - 1005 29 October 2010 (Rev. 1 February
2011)
"An Radiant Barrier System (RBS) with a 3.5" gap
has a performance that varies significantly between operating at
a temperature of 140 °F (i.e., a solar heated roof sheathing)
with an R-value of about 10 and a temperature of 0°F (a cold
winter night) with an R-value of only 2.5. Add additional
variables such as dirt accumulation on the barrier and a wide
range of performance values can be quoted. In most cases, the
annual benefit of an RBS relative to an inch of insulation is
small or non-existent:"
U.S. Department of Energy, Radiant Barriers, 2011
"Of course, installing them at all in a cold
climate is not generally cost effective anyway".
Canadian Standards Association CAN/CSA-F280 Determining
the Required Capacity of Residential Space Heating and
Cooling Appliances, Table 7B Procedure
for Calculating RSI Values
"Reflective Films: A common mistake in
RSI value calculations is the assumption that reflective films
contribute thermal resistance in all building assemblies that
incorporate them. In fact, reflective films contribute
resistance only when they are facing an air space, as it is only
then that radiative heat transfer becomes at all significant.
Thus, a reflective film sandwiched between two other materials
will make no significant contribution to the thermal resistance
of an assembly."
Nova Scotia Building Code 2011
Section 10.3.2. Thermal Insulation for Buildings of
Residential Occupancy, item (3)"Reflective surfaces of
insulating materials shall not be considered in calculating the
thermal resistance of building assemblies."
Madison Gas and Electric Company, 2011
Reflective foils without an air space have an equivalent
R-value of 0.
Manufacturers’ claims for the R-values of reflective
insulation need to be examined closely, because the
R-value can change depending on where the insulation is
used.
Ontario Building Code 2012
Section 12.3.2. Thermal Insulation for Buildings of
Residential Occupancy, item (3)"Reflective surfaces of
insulating materials shall not be considered in calculating
the thermal resistance of building assemblies."
Ontario Building Code 2012 -
Supplementary Standard
SB-12, Energy Efficiency For Housing, January 1, 2012
update: Section 2.1. Methods for Achieving Energy Efficiency
Compliance, 2.1.1.1. Energy Efficiency (5) "Reflective
surfaces of insulating materials shall not be considered in
calculating the thermal resistance of building assemblies."
FTC Action Leads to Court Order: Home Insulation Marketer
to Pay $350,000, January 31st, 2013
A federal court ordered a home insulation
marketer to pay a $350,000 civil penalty for making
deceptive and unsubstantiated claims about his products’
insulation capabilities. On the Federal Trade Commission’s
behalf, the U.S. Department of Justice won the order on the
merits of the case without a trial. The $350,000 figure is
the largest civil penalty awarded in a home insulation case.
Edward Sumpolec, doing business as
Thermalkool, Thermalcool, and Energy Conservation
Specialists, violated the FTC Act and the agency’s Rvalue
Rule in selling liquid coating and
foil radiant barrier products. Sumpolec’s advertising
included false claims such as “R-100 paint,” “This . . .
reflective coating will reduce wall and roof temperatures by
50-95 degrees . . .” and “Saves 40 to 60% on your energy
bills.
The Minnesota Department of Commerce, Division of Energy
Resources, April 10th, 2013
"The Minnesota Department of Commerce, Division of Energy
Resources has issued an alert to consumers who are
considering the purchase of
radiant barriers in their attics. The Commerce
Department, which has received recent reports of salespeople
pitching the radiant barrier product in flyers and at free
dinners throughout Minnesota, warns consumers that radiant
barriers are not a cost-effective way to reduce heating or
cooling loads in Minnesota"
Other Sources
De-rating Recommendations for Reflective Aluminium Foil Insulations As a
Result of Dust Accumulation
by Dr. R.M. Aynsley
Energy Efficiency Factsheet, Principles of Heat Transfer
by Dr. C. Roos.
HPAC Engineering, Moisture, Materials, and Buildings by Dr, J.F. Straube
Radiant Panel Association Technical Bulletin 101 (for members)
Radiant Panel Association Technical Bulletin 220 (for members)
Department of Energy, DOE/CE-0180/with Addendum 1, Insulation Facts
CSA B214-01, Installation Code for Hydronic Heating Systems
ANSI/ASHRAE Standard 90.2-2004, Energy-Efficient Design of Low-Rise
Residential Buildings
Part 1, Answers to questions on snow-melt insulation
by
Mark Eatherton
Part 2, More answers on snow-melt insulation by Mark Eatherton
Part 3, Even more answers on snow-melt insulation by Mark Eatherton
Field Results of Insulations in a Snow Melt System, by Mark Eatherton
Underslab Insulation for Radiant Heating, Dr. J. Straube, C. Schumacher,
B.Tech, B.A.Sc. for Beaver Plastics, 2000
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