[ThermaCoustic] TC-417-GP / Steel roof systems

Home Products Links Prospects Contact us

TC-417-GP Thermal and Acoustic Solutions
Spray Applied Insulation
SECTION 07210
b) ADDING TC-417 GP TO STEEL ROOF SYSTEMS

NOTES:

Please be aware that, in any climate where freezing temperatures are encountered, and in any conditioned building, at least 66% of the total insulation value must be on the cold side of the vapour barrier. This is to prevent condensation forming on the inside of the structure;
For a complete explanation on preventing condensation within interior roof insulation, please refer to our GENERAL INFORMATION section, sub-heading CONDENSATION CONTROL;
The foregoing is a general 'rule of thumb' that can be safely relied upon in most of the cool temperate parts of the world. However, we recommend that, to be sure of the proportions required in any given area, a competent, local HVAC engineering firm be consulted;
In warmer climates, the situation changes. As general ambient temperatures increase, the percentage of insulation placed on the outside (cold) side of the roof skin can be decreased. Eventually, in the case of very hot climates where cooling the building is the major concern the cold side of the vapour barrier becomes the inside of the building. In those circumstances all the insulation should be on the inside surface of the roof.

It should be noted that:

In a single skin steel roof assembly with exterior insulation placed on top of the roof panels, they act as the vapour barrier;
In a double skin assembly, the lower panels act as the vapour barrier. The upper skin is separated from the insulation by a ventilation channel to eliminate the possibility of condensation in what is, effectively, the exterior insulation.

In some circumstances, it may be desirable to:

Add more insulation to an existing roof assembly. For instance:

To meet upgraded energy code requirements;
To improve the effective value of the nominal R (RSI) value of the insulation package. All insulation materials transfer heat by a varying combination of radiation, convection and conduction. By placing some insulation on the warm side of the vapour barrier, heat loss by convection to the outer insulation is blocked by the vapour barrier.

Lower a roof profile by reducing the thickness of the external insulation;
Improve the building's acoustic performance by adding TC-417 GP to the underside of the roof.

In the examples cited above, TC-417 GP can be safely employed as long as our guideline, or overriding professional advice based on specific local conditions, is followed.

[Previous] [Contents]

[Home] [Products] [Links] [Prospects] [Contact us] [Disclaimer]

ThermaCoustic Industries International Limited
Unit 108, 20119 - 113B Avenue, Maple Ridge, B.C., Canada, V2X 0Z1
Tel: 866.460.1474 or 604.460.1475 -- Fax: 604.460.1476 -- eMail: info@thermacoustics.com