Aerated concrete for building in Spain: uses, limitations and system costs

You may know aerated concrete from houses in your home country and want the same material for a Spanish build. That familiarity is useful, but it is not a specification. The local design, available product range, installer’s method and finished wall arrangement all need to line up before the price means much.

This guide concerns autoclaved aerated concrete masonry units, often shortened to AAC. Spain’s CTE DB-SE-F includes this masonry family and references the relevant product standard. That does not make a particular wall suitable for every building: the designer still needs to establish its role and performance.

Ask what the wall actually does

Start with three separate questions. Is the proposed wall carrying structural loads? Is it an external infill wall within another structural frame? Or is it an internal partition? Get the answer marked on the drawings. A supplier’s description of “building blocks” leaves too much unresolved for procurement.

Request the exact product and dimensions rather than accepting a brand alone. Ask which components form the associated system and which are supplied by others. If you are switching from a design already completed in another material, have the architect identify the revisions before asking contractors to tender the change.

For a wider decision between methods, compare the procurement implications in our guide to modular, prefab and traditional construction in Spain. The right question is how a complete house will be delivered on your plot, not which wall looks simplest in a demonstration.

Use a wall schedule instead of a block-price comparison

A useful schedule identifies each wall type, area, height, openings and finish. It should state the layers from the outside face to the inside face and allocate responsibility for junctions. Ask the contractor to price against that schedule so the quote describes something you can recognise on site.

Clarify the measurement rule. Some quotes deduct openings but charge their edges separately; others use a different basis. Neither approach should be left implicit. Comparing the same finished elevation avoids rewarding the quote that simply leaves the most details unpriced.

Separate product data from whole-house performance

Ask the designer how the selected wall contributes to the building’s energy assessment. Spain’s DB-HE resources cover the envelope and include support documents for thermal bridges and condensation. A product’s thermal value is only one input to that work.

For an overseas owner, a particularly useful request is an annotated junction drawing. Where does the wall meet the floor edge? What happens around a shutter box if one is planned? How does the window connect to the wall finishes? These drawings make it easier to compare contractors and to discuss what must be inspected before it is covered.

Use the same discipline for acoustic or fire-performance claims. Ask which documented assembly the claim refers to and whether your proposed wall matches it. Avoid extrapolating a result from a different thickness, finish or configuration. Your technical team should handle that assessment.

Bring the kitchen, bathroom and equipment layouts forward

Wall construction becomes more complicated when heavy fixtures are considered late. Give the design team a list of wall-hung furniture, bathroom equipment, shading and other attachments. Ask them to specify the support arrangements and to show who provides any dedicated components.

This is also the moment to agree service routes. A clear design helps the masonry contractor and the electrician or plumber understand where openings belong and when approval is required for changes. Do not let a late design choice become an undocumented site improvisation.

Evaluate the installer’s proposed process

Ask who will supervise the work and which installation instructions the team will follow. A useful answer explains sequence, checks, coordination and the contact for technical queries. A photo of a past wall says much less. If the contractor offers a reference project, ask whether they supplied the material, installed it or delivered the entire building.

Compare programme milestones consistently. “Walls erected” is not the same stage as a weather-complete envelope or an interior ready for finishes. Request the dependencies and remaining tasks at each milestone, especially if your accommodation plans depend on the completion date.

Compare the complete installed wall cost

The useful figure is the installed price for your defined wall package in your municipality. It should include the components and interfaces in the design, not just blocks multiplied by area. Ask for supply, labour, site logistics and exclusions to be visible even if the contractor also offers one total.

Some decisions affect adjacent packages. A changed wall build-up may require a review of window details or façade finishes. Price those consequences before judging the saving. Use the broader house-building budget structure to keep the wall choice in proportion to the full project.

For exterior finish options, our external insulation guide explains another complete-system comparison. Do not add such a finish by default; have the designer establish what the chosen wall actually requires.

Your decision checklist

1. Confirm the wall’s function and exact product with the designer.
2. Agree the complete build-up and the important junction details.
3. Price supply, installation, finishes and logistics on one measurement basis.
4. Identify who coordinates service openings and fixture supports.
5. Check the installer’s method, review points and programme milestones.
6. Approve substitutions only through the agreed technical process.

Aerated concrete becomes a meaningful option when these questions have answers. You do not need to become a masonry engineer; you need a defined scope, a responsible design team and a quotation that follows their drawings.

Coordinate the base of the wall with the floor construction, including any ventilated crawlspace. For structural concrete elsewhere in the project, the reinforced-concrete cost guide separates the mix from reinforcement, formwork and execution.

Tell us about your Spanish building project, including the municipality, design stage and whether you need material supply or a complete wall package. Mention any existing drawings so the request can start from the work already done.