With the benefit of many years experience in the design of successful low – energy usage structures, the architects and engineers at Algarve Gold have taken a fresh look at how houses are commonly built in the Algarve.
Our professionals have set out specifically to solve the problems relating to condensation and thermal retention often found in a climate where seasonal day/night temperature variations can be dramatic.
Factors considered include the following:
- Availability of materials
- Aesthetic appearance
- Humidity control and condensation protection
- Thermal confort
- Energy saving
- Strength, durability and maintenance
- Natural sustainable materials / low embodied energy content
There is nothing revolutionary in the solutions proposed to address these factors. Our preferred specification employs well-proven techniques and materials, based on structures built using adobe or clay bricks, materials that have been in continuous use for millennia. This specification can also include use of the concept of the plenum as a means of distributing heat, a system devised by the Romans for domestic heating over two thousand years ago.
The principal structural frame for properties designed using our preferred specifications consists of reinforced concrete beams, which in turn are supported by concrete columns set in individual concrete pad foundations. This type of reinforced concrete frame provides excellent earthquake protection.
In such a structure, ground floors are suspended over a plenum or sub-floor trap and are fabricated using concrete beams and blocks finished with a structural concrete topping and screed. The plenum allows warmed or cooled air to circulate freely under the floor and through wall vents into the rooms. Inner wall bases incorporate openings for air circulation within the plenum. The floors and walls of the plenum incorporate a damp proof membrane and of expanded polystyrene (EPS) insulation.
Outer walls consist of an inner layer of adobe blocks finished with clay render, an outer layer of hollow terracotta blocks, and external cork insulation finished with a layer of mineral silicate vapour-permeable render. EPS with an acrylic render is available as a lower cost alternative to cork.
Outer walls are protected by a damp proof course and supported by a reinforced concrete sub-wall with EPS external and internal insulation to prevent heat losses.
Inner walls consist of either single leaf adobe block with clay render both sides, or full width adobe block with clay render both sides.
Our recommended roofing option employs sandwich panel systems comprising layers of treated timber and EPS. Cork can be used as an alternative to EPS. Panels are covered by a waterproof breathing membrane. A Portuguese barrel tile system is then installed over battens on counter battens to ventilate the roof.
As large windows can contribute to heat-loss in winter and excessive over-heating during summer, application of correct window technology is critical. We consequently recommend use of double-glazed windows incorporating thermal breaks to inhibit heat transfer between the inner and outer surfaces, and trickle vents, to help eliminate the risk of condensation, while windows with high solar exposure should be fabricated high performance glass to inhibit solar gains.