What You Get and What it Costs

A Brief Look at Our Materials and Techniques

Here are some of the materials and methods which we prefer to use. The building we suggest for you and your site will be unique to you and may include some or all of these elements.

Note that different environments may require quite different combinations of materials and building techniques. For example our own region of Granada has a number of quite different micro climates. The coastal area is mild all year round and the sea air is clean and healthy. This may require a quite different specification and design to a site close to Granada city, where it can be very hot in the summer and very cold in the winter.

A Timber Frame. A timber frame outperforms a concrete and steel structure in almost every way. It is greener, faster, more economical, more flexible, safer, lighter and easier to assemble on site than concrete and steel.

Note that a timber frame is not a wooden building. We have written an article on the website outlining in detail the benefits of a timber frame and exposing some of the common misconceptions.

A Hermetic Seal. This is an important feature of a low energy building because it allows you total control over the temperature inside the building. Combined with an HRV (Heat Recovery and Ventilation) it allows you total control over the purity and humidity of the air. The degree of hermetic seal will vary according to the energy balance of the building, your budget, preferences, and other circumstances.

Heat Recovery and Ventilation System. (HRV) A mechanical ventilation system extracts dirty air out of the kitchen and bathroom. Filtered fresh air from outside is introduced into the bedrooms and living spaces. The outgoing air exchanges heat with the incoming air to about 96% efficiency. This works in one direction during the winter and in the other direction during the summer. So you are always breathing fresh filtered air at the right temperature regardless of the temperature outside. You can also control the humidity by controlling the rates of air exchange.

A tight hermetic seal and HRV work together keeping you warm in winter and cool in summer. Of course you can open the windows, but you won’t want to when conditions are either very hot or very cold. If your local climate is mild and the air clean and fresh we may recommend that you opt out of these systems. Alternatively you may want to incorporate them in your building and use them only during certain months of the year when the conditions are extreme.

Super insulated walls both exterior and interior. There should be almost no heat passing through an external wall in either direction. Internal walls are also sound proofed. The actual materials used may vary depending on the energy balance of the building and your preferences and budget. We favour cork, which is sourced locally, or hemp which is a little less expensive.

Absence of Thermal Bridges. A thermal bridge is a fast conducting route between the outside and the inside of the building. Thermal bridges in new buildings often occur because not enough thought has been put into the detail of the design. Unaware workers and craftsmen may unwittingly create them.

Super Insulated Windows. Until recently windows were the thermal weak point in any highly insulated building. These days you can have plenty of natural light and enjoy the views because of super insulated windows. The specification that we recommend i.e. the glass, the frame and the join will vary depending on the energy balance of the building and your budget. Top of the range triple glazed argon filled windows with a system which prevents thermal bridge are the ideal.

Again you could choose to relax the specification here if your climate is mild, such as on the coast.

Shade and Shutters. Another key element of an energy efficient building, especially in a Mediterranean climate. You will probably want large shaded areas for outside living. You may want to combine large shaded areas with large windows or even glass walls.

Highly insulated shutters for shade and security are on the menu.

Solar Powered Heating, Cooling and Hot Water System. This technology is key to our bold claims about comfort during the hot Mediterranean summer. It is one thing to build a highly insulated house in a cold climate and use little energy to heat it. It is a completely different challenge to build a highly insulated house in a hot climate and use little energy to cool it. We have the solution!

The system in our sample home design includes a swimming pool as a heat sink.

Again, we would be likely to recommend this where the climate includes extreme temperatures in winter and summer and less likely if the climate is mild.

Renewable Energy Generation. Photovoltaic, wind powered, natural gas, and mini-hydro electricity generators are all options. So are geo thermal and solar water heaters. We begin by discussing with you your lifestyle and estimate the amount of power you will consume in your new home. We then develop an energy balance for the building which takes into account the energy efficiency of the design and materials, your  budget and preferences, the amount of energy we will generate from renewable resources and how to produce it.

You can even be 100% autonomous and generate all the power and energy you need.

Rainwater Harvesting and Grey Water Recycling. We encourage this and incorporate it into our designs as standard. Clients can opt out if they wish.

Green Roofs. This is an option where appropriate. We have used this solution successfully in a complex of bioclimatic dwellings for Iberdrola, the large Spanish wind power company. It is unsurpassed as a method of roof insulation, but doesn’t suit everyone as it does require some maintenance.

Low Energy Lighting and Domestic Appliances. We include these as standard. The installation and correct positioning are an important part of the energy balance of the building that we plan from the outset.

Security and Control. It is an optional extra, but we offer automated control systems. These can include entry detection and alarm systems which are connected to an external switchboard. It can also include precautions against fire, such as smoke detectors (also connected to a switchboard), timers for exterior lighting systems, or automated irrigation systems for the garden.

Sample Home Design

South elevation. Landscape: La Loma del Gato, Ítrabo, Granada.

South view. Landscape: La Loma del Gato, Ítrabo, Granada.

South-east view. Landscape: La Loma del Gato, Ítrabo, Granada.

Plant. Enviromental Treatment.

Cross section.

The Technical Standard Specification and Price

The specification list detailed below corresponds to the sample design home which is an illustration. Your specification, after extensive consultations with you, and a site inspection, will almost certainly be different and have a different price.

Technical Specification

Foundations. Reinforced concrete foundations HA-25-lla on a bed of compacted gravel and ballasts. If the ground conditions are unstable we would have to examine specific solutions at an extra cost.

Structure. Timber frame structure of beams and pillars joined by wooden or galvanized steel joints.

Roofs. A flat roof constructed with a timber frame covered with ’sandwich’ type panels. The interior will be wooden paneling or plastered gypsum board. The sandwich panels are made up of layers of insulation, vapour barriers and PVC waterproofing, and a layer of gravel will be laid over the exterior face. The roof has an air cavity which removes heat by convection in summer and which can be closed in the winter to improve insulation.

External Walls. An external envelope consisting of layers of water-resistant fibre cement board. The exterior layer features a ventilated outer layer solution, which can be protected from exposure to the elements using synthetic paneling, 2cm thick stone panels, or aluminum composite panels. As well as the ventilated cavity, the external face features a minimum of 6cm of thermal insulation. The interior layer is a combination of panels of different densities which ensure the best thermo-acoustic insulation.

Insulation. The thermal insulation of the house is based on cork panels fixed to rigid boards in the roof and external walls. Vapour barriers are used to prevent condensation. An alternative is natural fibre –such as hemp panels.

Interior Walls. Interior wall linings and internal walls are modular panels dry mounted with thermal and acoustic interior insulation. All the plumbing, electric cables and communication cables run within the walls, and are easily and quickly installed.

Internal Wall Finishes. The final finish to the panels could be hardwood tongue and groove paneling or water based solvent-free (low VOC) paints. Wallpaper is a possible alternative.

Windows. High quality windows framed in timber, aluminum or pvc with thermal bridge breaks. They are air filled double glazing, and the glass has a metallic oxidized treatment (Planitherm or equivalent) which markedly reduces solar heating in the summer and reflects interior heat back inside in winter. Added extra could include Climalit Bioclean self cleaning (low maintenance) windows.

Doors. Solid wood interior doors with stainless steel door furniture. Exterior doors are reinforced with steel plate and high security locks.

Floors. Tongue and groove laminated flooring available in a range of natural wood finishes. This flooring material is extremely resistant to abrasion, scratching, burns from cigarettes or flame. It has a quality feel to it in both winter and summer. Skirting boards are in the same finish.

Bathroom Fittings. Top of the range sanitary fittings and taps in prestige materials. Mirrors, towel racks etc are all included.

Kitchen. The specification includes all kitchen furniture and low energy consumption domestic appliances: fridge, freezer, cooker, extractor fan, washing machine, and dish washer.

Plumbing and Cables. All plumbing and cables run through the interior of the walls. Water supply pipes are of reticulated polythene. Waste pipes of Polypropylene PEX.

Rainwater harvesting. A system to collect water from the roof in a subterranean cistern is included. This water could be used for irrigation purposes.

Lighting. Low energy lighting is included throughout.

Heating and Hot Water. Includes a mixed system of solar panels for hot water, and under-floor heating with biomass as an energy source. In our example it is assumed that the building is connected to all main services, including electricity.

Security System. A security system with movement detectors and alarm is included.

External paving. The house is surrounded by a 1.5 metres band of stone paving.

Swimming Pool. A 30 square metre polyester swimming pool is included.

Price and What’s Included / Excluded

The price of the sample design home  is 1995 euros per square metre.

Remember that you will receive a design and specification which is unique to you and your site, so the cost of your building could be more orless than this example.

What’s Included In The Price:

• Standard foundations, as per technical spec.
• Construction of the whole building, including mechanical equipment and energy saving devices described in the specification.
• Kitchen, bathroom, domestic appliances, lighting, interior decoration, security system, and swimming pool.
• Quality control supervision for building materials and execution.
• Final quality supervision and legal certificates for the insurance company.
• Ten year building guarantee.
• Architects Fees (steps 4, 5, and 6).
• Quantity Surveyor’s fees.
• Engineers fees for certifying the mechanical appliances and installations.
• Project management.
• Dealing with the bureaucracy – planning consent and all licenses.

What’s Excluded In the Price of Our Design Concept

• Cost of the land and costs of acquiring the land.
• Extra costs of site preparation if necessary.
• Topographical site survey and geotechnical report to determine the properties of the ground under the building.
• Special foundations or retaining walls, which may be required because of the nature of or topography of the ground.
• Landscaping and garden setup.
• Legal fees.
• Taxes.