Aqua-Therm brochure (1.2)
Product list Next brochure (2) Previous brochure (1.1) Price List Order Form
Tel. (Pta) 0861 777 460 or 081 5959 604 Fax. (Pta) 086 652 6752 e-mail (Pta) email@example.com or firstname.lastname@example.org or email@example.com
P.O.Box 123 Laezonia 0026 (Pretoria) Web address: www.cosmodec.co.za
Package - 15 kg`s, Price – R1,698.00.00 (Smaller packs add 50%)Coverage approx. 45 sq. meters for 1 coat (R40.00/m sq) and 25 square meters for 2 coats.(R70.00/ m sq) Excl.VAT .and delivery.
Aqua-Therm is a specially formulated two pack coating system designed to provide the customer with the best of both worlds when it comes to waterproofing and thermal insulation of structures, specially concrete roofs.
Aqua-Therm stops thermal shock (The expansion and contraction of roofs) thus eliminates cracks forming in roofs (particularly concrete) a major source of
Aqua-Therm is a wonderful vapour barrier thus adding substantially to it`s cooling ability.
Pack one contains, among other elements, the active ingredient for cooling (Thermal insulating) and porcelain and pack two consists of the unique resin blend (Liquid plastic) designed to hold everything together, and provide exceptional longevity, adhesion, uv resistance, waterproofing etc.
Aqua-Therm, is, once mixed according to instructions below, applied by brush, roller or spray applicators.
Aqua-Therm is water based, thus environmentally friendly.
No more expensive torch-on systems. Aqua-Therm takes the place of this, at a fraction of the cost and is much more effective. It can even be done on a DIY basis.
Cosmo-Dec`s hi tech approach to it`s coating technology means we are always at the forefront when it comes to new innovative ideas.
Our coatings contain active ingredients that literally clean the air.
Ensure that the substrate is clean, dry and stable before application of Aqua-Therm. There is generally no need for a bonding liquid since Aqua-Therm is in itself an exceptional bonding agent. (Check with Cosmo-Dec first, providing details)
If coating onto screed, plastered surface or porous concrete, wet the surface slightly before applying Aqua-Therm. This gives a better spread rate and aids in penetration and adhesion.
Add three parts of powder to two parts of liquid in a vessel. (Or 1 to 1) Stir for a couple of minutes or until there are no lumps. A paddle in a hand held drill works well. Mix about 5 to 10 liters at a time as the mixture has a pot life of about 45 minutes. One can also mix the product 2 powders to one liquid or even 1 to one. See which works best for the surface you are applying onto.
For roller or brush applications use uni directional strokes on the entire surface, thereafter , at right angles to the first coat, apply a second coat. More coats may be applied according to the substrate. Drying time is quick, about 30 minutes. The second coat may be applied soon after the first coat has properly dried. Aqua-Therm will stick to most surfaces such as, concrete, asbestos, steel, iron, aluminium, most plastics, etc.
Flat concrete roofs.
Corrugated iron roofs.
Animal shelters - floor or roof.
Any application where waterproofing and/or thermal insulation is required.
Aqua-Therm is washable acid resistant, chip and crack resistant, as well as resistant to blistering peeling or flaking.
Reduces thermal shock
Prevents cracking of slab (Substrate)
On iron roofs stops rust
Vapour barrier (A major aid in enhancing cooling)
Reduces air conditioning running costs
Pays for itself in months
Aqua-Therm comes in 20 kg packs (Powder and fluid together)
One to two square meters per kg. per coat depending on the substrate.
Most pastel shades can be blended but generally white works best.
Previously leaky dilapidated roof sealed with Aqua-Therm.
Magnificent example of Aqua-Therm at its wonderful best
Concrete flat roofs being waterproofed and cooled
Special roof coatings can save energy in hot climates and can help utilities in warm climates reduce peak demand.
Architects are using special coatings to cool off buildings in hot climates, but until recently there was little research on the measured cooling-energy savings of these roofs.
Over the past two years, however, researchers in Florida and California have examined the impact of these roof coatings on air-conditioning energy use in retrofits of monitored homes. Simulation analysis suggests that a specially coated roof can cut a building's cooling load by 10-60%. The higher numbers are associated with uninsulated roofs.
Cooling coatings are increasingly being used for manufactured homes in the Southeast, based on homeowner reports that such coatings can reduce summer air conditioning costs. Until now, however, no investigation in a cooling-dominated climate examined the effect of coated roof on time-of-day air conditioning electrical demand in occupied residential buildings--important information for utilities where summertime peak demand is a concern.
One of the earliest whole-building studies that measured cooling-energy savings from cool roof coatings was performed by the Mississippi Power Company. The utility monitored two identical side-by-side single-story commercial office buildings after the roof of one had been covered with a cooling coating. Both existing buildings had R-11 roof insulation. The results of the experiment? Summertime air conditioning was reduced by 22% in the building with the reflective roof coating.
More recently, researchers at LBL measured very significant cooling-energy savings from applying cooling coatings to three buildings in central California . At one site, energy demand for space cooling was nearly eliminated. But regardless of the potential of cooling roof coatings in California, Florida's higher humidity and nighttime temperatures make prospects for near elimination of space cooling energy use in that state very unlikely.
An Initial Experiment
In the summer of 1991 we conducted a preliminary experiment in Merritt Island, Florida. Our first test building (Site #0) was a 1,800 ft2 detached single-family, single-story home of conventional concrete-block construction. The pitched roof faced north-south, with plywood decking covered by green/gray asphalt shingles. The home's attic was well insulated with approximately two inches of fiberglass covered by an additional six inches of cellulose insulation, yielding a thermal resistance of about R-25. Air infiltration from the attic area into the conditioned interior (a common problem due to duct leakage), had been largely eliminated in a previous audit and retrofit. Beginning in May 1991, we submetered the home's air conditioner while maintaining a constant thermostat setting of 79deg.F. We also recorded the underside roof deck, attic air, and living room temperatures.
When we applied the cooling coating on September 5 of that year, the roof's reflectivity increased from 0.22 to 0.73.2 Spot measurements under full sun at midsummer had shown shingle surface temperatures of 160-170deg.F, prior to the roof treatment, compared to 110deg.F after we applied the coating. Analysis assuming an 81deg.F average summer temperature indicated that a cooling roof coating would reduce energy consumption by 10% (35 kWh versus 39 kWh per day).
Yet this test house probably understated the savings, since most existing Florida residences have fairly poor attic insulation and attic air frequently leaks into the conditioned interiors. Therefore, we obtained more "typical" residences for the detailed experiments we conducted the following year.
A Five-House Follow-up
To learn about how cooling roof coatings affect peak cooling demand we measured the 15-minute air-conditioning electricity demand in our follow-up study, along with meteorological conditions for three weeks before and after each home was retrofitted. We also used infrared thermography to examine how interior heat fluxes from the roof/ceiling were altered by the retrofit.
With equipment to instrument two buildings, we sought one residence with typical ceiling insulation levels (approximately R-11) and a second structure without any insulation at all. (Many homes built in Florida prior to 1965 have no attic insulation and were built with flat roofs that make retrofits difficult.) Data from Site #1 would be used to obtain results from a more-typical existing residential building, while Site #2 would help us define the maximum savings potential for cooling roof coatings in Florida. Experiments on three more houses in the summer of 1993 extended our sample size. Each house in the second round of experiments had unique characteristics that broadened our knowledge of how cooling roof coatings reduce air-conditioning needs.(Table 1)
Site #1 was a fairly typical existing Florida home. The attic was insulated to approximately R-11, but the air conditioner was old and inefficient. Although pre- and post- application air temperatures and solar radiation were comparable, air-conditioning power demand was reduced by an average of 25% (from 40 to 30 kWh per day) after we applied the roof coating. The average electrical consumption of the air conditioning system during the utility coincident peak period (5-6 pm) was 2.4 kWh before the coating and 1.7 kWh afterward. This 700 W savings represents a 28% reduction in peak power demand attributable to the coating. Furthermore, average 24-hour attic air temperatures were reduced by 6deg.F, while peak attic temperatures between 2 pm and 6 pm fell by an average of 15deg.F.
Site #2 was an ideal candidate for a cooling roof coating. The house had a flat roof and no space was available to insulate the ceiling assembly. Prior to the coating, the 2.5-ton air conditioner was unable to control the interior temperature adequately, running continuously each day from noon until 7 pm when the thermostat was finally satisfied.
Average air-conditioner electricity consumption dropped from 36 kWh to 20 kWh per day after the application--a 43% reduction. Savings would have been higher if the house had possessed a larger air conditioner, but the results did demonstrate the huge potential for gaining cooling-energy savings by applying a cooling roof coatings to the roofs of homes without ceiling insulation.
The temperature reductions to the deck, deck airspace and ceilings were also striking, as was the change in the air conditioner's load profile. Before the retrofit, the daily interior temperature had ranged above the thermostat set point by 4deg.F or more. The average electrical demand of the air conditioning system during the utility coincident peak period (5-6 pm) was 2.2 kW before the coating and 1.4 kW after the application--a 38% reduction.
Site #3 was a small house, cooled with a through-the-wall air conditioner. Since there was no attic duct system the site was of unique research value. The attic above the dropped ceiling contained no insulation, and the 1.5-ton air conditioner ran constantly prior to the coating (from 1-10 pm) unable to satisfy the thermostat. After the coating, the air conditioner cycled on and off during the same time period, maintaining improved interior comfort while reducing the utility coincident peak demand (5-6 pm) by nearly 960 W. Total daily air conditioning use was 11.9 kWh lower after the coating was applied--a reduction of 47% under peak-day conditions. After the retrofit, the average daily air conditioning savings totalled 5.6 kWh, or 25% during the summer period (Table 1) and peak demand savings averaged 30% (500 W).
We selected Site #4 to see how applying a cooling roof coating to a gravel roof (common in South Florida) might reduce energy use, and also because the household complained of high utility bills. The ceiling was well-insulated for a Miami home (R--11-R-19 blown fiberglass) and its 3-ton air conditioner was relatively efficient. But while auditing the home, we found a large duct-system supply leak in an inaccessible portion of the attic. (We found the leak with an infrared camera.) The leak was not repaired, but the roof was later coated with a cooling roof coating. Although the percentage savings of air conditioning energy (15%) were lowest at Site 4, the absolute savings of 8.0 kWh per day were nevertheless significant.
Site #5 had a tile roof, but the cement barrel tiles were old and stained a dark gray. The house also had relatively poor ceiling insulation and an inefficient air conditioner. The measured solar albedo was 20% before coating, but after being coated with a sprayed-on cooling coating, it was 64%. The absolute savings at this site were quite large at 11.6 kWh per day with a 988 W reduction in coincident peak-cooling demand.
Reflecting on cool roofs
Cool roofs can reduce space-cooling energy consumption and demand in Florida. Data collected so far suggest that air conditioning savings of 10-40% can be realized, with the larger reductions associated with poorly insulated roof assemblies or buildings with excessive attic air infiltration due to air handler return air leakage. cooling coatings may be particularly suitable in existing residences where the roof structure makes it difficult to add insulation.
Average electricity consumption for central air conditioning in single family homes in Florida is approximately 4,400 kWh/year. Based on a savings level of 10-40%, cool roofs can be expected to reduce household electricity use by 440 to 1,760 kWh per year--an annual savings of $35-$140 at current electricity rates (assuming 8cents per kWh). Obviously, the savings will vary depending upon the severity of the cooling season.
What About the Payback?
A frequent question concerns payback of cool roofing. There are several angles on the answer, but generally speaking, cooling coatings are most appropriate when one is re-roofing. If the coating is applied to an existing roof that is in otherwise pristine condition, the cost equation is straightforward. The typical coverage of a cooling coating is 25 ft2 per gallon,(0,6 sq. meters per liter) (Sno-Cote® gives 6 square meters per liter reducing the application cost factor by a factor of 10!!!! This makes a massive difference to these calulations and results) based on an application of two coats to a target thickness of 40 mils.
Cost for the material from vendors varies by 50% or more but averages about $60 per 5-gallon container when purchased in quantity. It is important to keep in mind that roof area is generally considered greater than building floor area, particularly with a steep roof pitch. For instance, a typical 1,500 ft2 home may have 2,200 ft2 of roof to be covered. The application then requires 90 gallons of coating material for a materials cost of approximately $1,100.
The cost of labor for installation depends greatly on the roof surface, on whether the coating is to be rolled on or sprayed, and on labor rates. A typical labor cost might be approximately 50cents per ft2 for the required two applications. Thus the overall application would cost about $1 per ft2, or approximately $2,200 for a typical home. With annual energy savings in Florida of $35-$140, the payback times are long--usually lasting longer than the roof itself.(With the exception of Sno-Cote®)
A completely different scenario emerges if the home is soon in need of re-roofing, however. Here the roof coating (which essentially creates a new weatherproof surface) might be seen as a way of extending the life of the roof by 5 to 10 years at half of the cost of re-roofing. The energy savings then become a side benefit.
For new homes, the situation is even more interesting. Here it is often possible to choose roofing types--such as metal roofing, tile roofing, or metal or ceramic shingles--that can be specified in a reflective white at significant additional cost. Unfortunately, no truly reflective asphalt roofing shingles yet exist for the residential market, but this situation may change as researchers work with the roofing industry to develop new products and spread the word about the energy benefits to help create a market for the materials. For commercial buildings, a variety of reflective roofing materials are already available: Hypalon, white EPDM, and PVC single-ply membranes. Once such products are widely available for the residential market, the economics may be significantly altered as the cost of reflective roofing becomes inconsequential. n
1. Reflectivity or albedo is the hemispherical reflectivity integrated over a particular wavelength band of the electromagnetic spectrum. For the purposes of this article, the terms reflectivity and albedo are used interchangeably and refer to the wavelengths encompassing the range of solar irradiance from 0.28 to 2.8 microns.
2. Surface solar reflectivity is measured using a precision spectral pyranometer with the device alternately faced upward towards the sun and downward towards the roof to determine the ratio of incident to reflected solar radiation.
Urban Heat Islands
Large cities typically contain darker surfaces and less vegetation than rural environments; these circumstances increase solar gain and thereby raise summertime cooling-energy demand. The dark surfaces and lack of vegetation also warm the summer air, leading to the creation of the urban "heat island." In fact, the average temperature in a typical city on a clear afternoon can be 1deg.F-5deg.F hotter than that of the surrounding rural area. Researchers at LBL Heat Island Project estimate that the additional air-conditioning use caused by this urban air temperature increase is responsible for 5%-10% of urban peak electric demand, at an annual cost of several billion dollars.
The power needed to compensate for these higher temperatures requires additional generating capacity, which often contributes to urban air pollution. Moreover, the elevated temperatures themselves accelerate smog formation. According to researchers with LBL, the probability of smog increases by 2%-4% per deg.F increase in maximum daily temperature. But shade trees and light-colored surfaces can offset, and may even reverse the summer heat island effect.
In one experiment, LBL examined the savings due to cooling roofing systems installed on three buildings in Sacramento, California. One was an occupied residence with R-11 ceiling insulation under a composite shingle roof. The initial roof reflectivity was measured at 0.18, and this was altered to 0.78 by application of acooling roof coating. Furthermore, the air-conditioning cooling load in the building was reduced by 69%, with a 28% reduction in peak electrical demand, and the seasonal energy savings amounted to a reduction of approximately 14 kWh per day and a 1 kW in peak power demand.
The second and third buildings were test bungalows. In both cases, the buildings' corrugated metal roof albedo was increased to approximately 70%, and measured air conditioning energy use was reduced by approximately 40%-50%.
Table 1. Results of Reflective Roof Retrofit Field Tests
|Energy use (kWh/day)||Reduction in utility coincident peak demand (5-6 pm)|
|Test Site and Description||Albedo before||Albedo after||Before||After||Savings|
Site #0 Merritt Island
Cooling coating on asphalt shingles, concrete block with R-25 ceiling insulation, attic duct system
|0.22||0.73||38.7||34.7||4.0 (11%)||Not Measured|
Site #1 Cocoa Beach
Cooling coating on asphalt shingles and flat gravel, R-11attic insulation, attic duct system
|0.21||0.73||40.6||30.3||10.3 (25%)||661 W (28%)|
Site #2 Cocoa Beach
cooling coating on tar paper; flat roof and no attic insulation, attic duct system
|0.20||0.73||35.5||20.1||15.4 (43%)||858 W (38%)|
Site #3 West Florida
Cooling coating on asphalt shingles, no attic insulation, no attic duct system
|0.08||0.61||22.4||16.8||5.6 (25%)||496 W (30%)|
Site #4 Miami
cooling coating for gravel roof, R-11 attic insulation, attic duct system
|0.31||0.61||51.9||43.9||8.0 (15%)||444 W (16%)|
Site #5 Merritt Island
Cooling coating on tile roof, R-7 attic insulation, attic duct system
|0.20||0.64||57.5||45.9||11.6 (20%)||988 W (23%)|
|Averages||0.20||0.68||41.1||31.5||9.2 (23%)||683 W (27%)|
How Long Will It Last?
Degradation of reflective roof coatings is of practical concern because their high-albedo property is primarily responsible for the cooling-energy savings. Cooling roof coatings may have good longevity when applied properly. For example, a five-year old swatch of an elastomeric coating applied to the cupola roof of the FSEC`s Passive Cooling Laboratory still showed a laboratory reflectance of 0.73--very close to the initial properties of such samples (0.70-0.79) The reflectivity of the roofs in FSEC's experimental homes was measured seven months after the coatings were applied. Some minor stains due to disintegrated leaves and dust were evident at Site #1, whereas no signs of degradation were in evidence on the flat roof at Site #2. The average of the measurements at Site #1 indicated a reflectance of 0.69 with greater variation in the readings over the roof surface. The tested reflectance at Site #2 was 0.73. Although both aged values were lower, a statistical test of the means revealed no significant differences in the data taken immediately after the coating were applied and those obtained seven months later. More recently, however, FSEC examined the roofs at Sites #1 and #2--18 months after they were coated. Although the flat roof at Site #2 still showed little sign of weathering, some staining was becoming apparent on the coated asphalt shingles at Site #1.
The most significant research on the longevity of cooling coated roofing systems was performed recently at LBL. This research examined 26 spot measurements of aged "high albedo" roofs of various types and found that most of the weathering and reduction in solar reflectance occurred in the first year after application or even within the first two months. For a gravel coating the albedo was reduced by 8% over six years, but 6% of the drop occurred in the first year. However, other reflective roofing types experienced reductions to albedo of up to 24%. The LBL researchers also experimented with washing cooling roofing systems, and found that it was possible to restore roofs to 90% of their initial values.
Figure 1a. Air conditioner use and interior air temperature before and after a cooling roof coating is applied at site #3.
Figure 1b. Temperatures before a cooling roof coating is applied at site #3.
Figure 1c. Temperatures after a cooling roof coating was applied at site #3.
"Must it Be White?"
Many considering the potential of cooling roof coatings are concerned about color. The FSEC has evaluated the solar reflectance of some 37 different roofing materials, with the measured data showing that white roof materials generally exhibit the best performance. They are highly reflective across the solar spectral bandwidth, while being highly emissive in the far-infrared region--this is another way of saying they strongly reflect solar heat and any heat they absorb will readily re-emit to the cooler sky temperatures. It may seem a bit counter-intuitive, but silver reflective aluminum paints do not perform nearly as well as others. This is because, although the aluminum flake paints have a high solar reflectance, they also have a low infrared emissivity--they tend to hold whatever heat they absorb--negating the cooling properties.
Fortunately, for those who demand non-white roof colors, it appears possible to tailor paints and pigments so they are not so reflective in the visible solar range, but are very reflective in the "invisible" near infrared region. The Navy has conducted research in this area to help develop infrared reflective coatings. Paints have been created that are twice as reflective in the near infrared as in the visible region. Researchers with LBL are examining spectrally selective paints that offer the possibility of significantly increasing the solar reflectance of even darkly pigmented colors. Physics suggests green-colored pigments with large particle size may further enhance the performance of solar reflective non-white paints. Even so, such coatings will not likely perform better than materials that are uniformly very reflective access the solar spectrum--particularly since the energy intensity of solar radiation is greatest in the visible bandwidth. Regardless, such developments promise to provide improved roofing materials with high albedo, while still preserving the designer's pallette of colors.
It may also be possible to tailor the properties of white reflective coatings to create superior performance. An ideal coating would be very reflective across the entire solar spectrum, while being very emissive in the long infrared region so that heat is readily re-emitted. Research shows promise in this area. One specialty coating, used to coat astronomical observatory domes, has a 98% solar reflectivity--so high that the temperature of the material is only slightly higher than air temperature under moderate solar intensity. Thus, it may be possible to tailor the composition of roof coatings to further optimize their performance.