Gulf Construction Online - Styrofoam is 'first choice of specifiers'

Insulation

Styrofoam is 'first choice of specifiers'

01 December 2001

Concrete blocks with foam insulation inserts are both economical and energy efficient, says Arabian Chemical Company (ACC) of Saudi Arabia.

ACC Polystyrene, which is a joint venture between Saudi Arabia's E A Juffali Brothers and Dow Chemical of the US, offers a wide range of Styrofoam thermal insulation products for the building industry.

The Styrofoam brand is a trademark of Dow Chemical.

"Thermal insulation is supposed to be an integral part in the construction of residential, commercial, industrial and institutional buildings," says Syed Ali Haroon, Eastern Province manager with the Dammam-based ACC Sales. "There are strict building insulation legislations in almost all Gulf states. "But unfortunately, due to a lack of a governing authority for the implementation of these standards, many developers ignore the use of wall insulation for residential and commercial buildings."

He continues: "The argument used is that since electricity bills are borne by the tenant, there is no incentive for them to use insulations in such buildings.

"However, buildings can be effectively and economically insulated using concrete blocks with Styrofoam. ACC, working with several concrete block manufacturers in the Kingdom, has developed a very economical block which uses Styrofoam extruded polystyrene foam as insulation inserts."

When put to the test, concrete blocks with blue Styrofoam foam inserts show higher r-values compared to those with white moulded bead polystyrene, he states. "Unlike moulded bead polystyrene, which has many voids between adjacent cells where moisture can collect and reduce the insulating values, the closed cells that make-up Styrofoam have no voids between each other," says Haroon.

"A water vapour diffusion test - modified Swiss standard SIA 279 which subjects insulation materials to temperature and vapour gradients over a 28-day exposure - has shown that moulded bead polystyrene absorbed about 30 per cent water by volume which resulted in a loss of about 70 per cent of its r-value. In contrast, Styrofoam retained 95 per cent of its r-value."

ACC says that the concrete blocks with Styrofoam have become very popular in the private villa market. "These blocks are currently being used for a 120-villas project for Kemya, a subsidiary of Saudi Basic Industries Corporation (Sabic) and for all new schools for the Ministry of Education," says Haroon.

The thermal performance of these blocks is further enhanced by using Styrofoam boards to eliminate the effect of thermal bridging resulting from the mortar joints in double wall cavity systems.

"Cavity wall insulation is the system of choice among specifiers," says Haroon. "The enclosed space between the inner and outer masonry walls is filled with Styrofam Wallmate rigid boards, which do not absorb moisture nor cause interstitial condensation. The tongue and groove on all four edges on the board eliminate thermal bridging."

Styrofoam, says Haroon, has thus become a key component in most insulation systems because of its excellent resistance to water and moisture absorption. "Its closed cell structure and negligible voids between cells enables the insulation to resist all forms of water penetration and thus maintain its r-value for the life of the building."