Ytong House

A Ytong house is a building whose load-bearing and non-load-bearing exterior and interior walls are constructed primarily or entirely from Ytong brand aerated concrete blocks. The term has become a colloquial name for houses built using aerated concrete, much like “Tempo” is used for tissues. Ytong houses are characterized by good thermal insulation, ease of construction, non-combustibility, and fast construction times, and are particularly widespread in self-build single-family homes and turnkey residential construction.

Construction and Building Method

Ytong houses are built using solid masonry construction, in which aerated concrete blocks are joined with thin-bed mortar (1 to 3 mm joint thickness) to form a homogeneous, low-thermal-bridge masonry structure. The blocks are dimensionally stable from the factory and can be easily worked by hand using a saw, planer, and router-which facilitates self-construction and simplifies finishing work. For exterior walls, block thicknesses of 36.5 to 50 cm are typically used to meet or exceed current thermal insulation requirements without the need for an additional external thermal insulation composite system (ETICS).

In Ytong houses, ceilings are often constructed using precast reinforced concrete elements (filigree ceilings) or as cast-in-place concrete slabs-meaning the ceiling structure does not differ fundamentally from other solid construction methods. The roof can be designed as a gable roof, hipped roof, or flat roof; in the roof area, Ytong is occasionally also used as infill for knee walls.

Another advantage in construction practice: Due to the low weight of the flat blocks (between 8 and 40 kg per block, depending on bulk density), the physical strain during masonry work is lower than with heavy sand-lime or clay blocks. This makes Ytong particularly attractive to DIY builders who wish to contribute a significant amount of their own labor to their construction project.

Thermal Properties and GEG Compliance

The distinctive feature of a Ytong house is its monolithic construction: a single building material simultaneously serves as a structural element and provides thermal and sound insulation. When using highly insulating aerated concrete types (lambda value 0.07-0.09 W/(m·K)) and wall thicknesses of 36.5 cm or more, GEG-compliant or even KfW-40 standards can be achieved.

Compared to other monolithic construction methods-such as vertically perforated bricks with ETICS-Ytong offers the advantage of a vapor-permeable, purely mineral-based construction without hazardous waste issues during demolition or disposal. For the Passive House standard (heating energy demand below 15 kWh/(m²·a)), the monolithic Ytong wall alone is generally not sufficient; an additional insulation layer or a very thick wall (over 50 cm) is required here.

The energy performance certificate for a Ytong house typically falls into energy efficiency classes A to B with modern block sizes and proper construction (especially details designed to minimize thermal bridges)-a value that can be highlighted as a positive feature during marketing.

Practical Tip for Homeowners in Nuremberg and Franconia

In Franconia, Ytong houses have been a common construction method for single-family homes since the 1980s. Anyone looking to buy a Ytong house should know the year of construction and the generation of blocks used at the time: Older homes from the 1970s to the 1990s often have thinner wall sections (24 to 30 cm) and poorer lambda values than today’s flat blocks. In such existing properties, retrofitting exterior insulation can significantly reduce energy consumption and improve the energy efficiency class-which has a positive impact on the market value.

As part of our assessment, we determine whether and which energy retrofit measures are sensible and eligible for subsidies, and we transparently highlight the qualities of a well-built Ytong house in the property description. A modern Ytong house is a compelling selling point, especially for buyers who value energy efficiency and plan for long-term operating costs.

Frequently Asked Questions

How long does a Ytong house last?

Aerated concrete is a mineral building material with a theoretically unlimited lifespan-comparable to other types of masonry. When constructed professionally and properly protected from the elements (plaster, paint), Ytong houses are designed to last for several generations. The practical service life used in property valuations is 80 to 100 years. This assumes that the exterior plaster is regularly maintained and that there are no conditions of persistent moisture that would damage the aerated concrete over the long term.

Is a Ytong house sufficiently soundproof?

Aerated concrete offers a certain degree of sound insulation due to its mass; however, because of its low bulk density, the sound insulation is lower than that of heavy brick or sand-lime brick. The rated sound insulation value of a typical 36.5-cm Ytong exterior wall is 47 to 52 dB-generally sufficient for outdoor noise in residential areas. For partition walls between residential units in multi-family homes, heavier building materials or double-wall constructions are recommended. Ytong offers special soundproofing blocks with higher bulk density (PP6-PP8) for this purpose.

Can I easily renovate a Ytong house?

Yes. Aerated concrete is very easy to saw, drill, mill, and fasten. Retrofitting slots for electrical and plumbing lines is straightforward. Heavy loads (shelves, kitchens) can be securely fastened with special aerated concrete anchors-standard wall plugs for lightweight walls are not suitable. Load-bearing walls may, of course, only be altered after structural approval-this applies equally to all solid construction methods.

How much does a Ytong house cost compared to other construction methods?

The construction costs of a Ytong house are comparable to those of other solid construction methods and are difficult to estimate as a flat rate, as they depend heavily on the floor plan, the specifications, and the region. The material cost of Ytong flat blocks falls in the mid-range; compared to vertically perforated bricks with ETICS, Ytong can be more cost-effective if the exterior wall does not require an additional insulation layer. In the Franconian region, regional Ytong dealers provide detailed cost estimates for your project.

What are the advantages and disadvantages of aerated concrete in terms of fire safety?

Aerated concrete is a non-combustible building material classified as Class A1 according to DIN 4102-it does not contribute to the fire load and does not emit toxic gases in the event of a fire. This is a significant advantage over insulation materials made of polystyrene or other organic materials. In multi-story residential construction, aerated concrete therefore usually meets fire safety requirements without additional protective measures. Anyone purchasing a Ytong house in Nuremberg or Franconia and planning renovations (e.g., converting the attic, adding a granny flat) can cite the documented fire safety quality of the aerated concrete with the relevant building authority-which can simplify the building permit process.

Valuation of Ytong Houses in the Real Estate Market

In property valuation, Ytong houses are treated like other solid-construction buildings: They are assessed using the asset value method, whereby building type, year of construction, and standard of finish determine the normal construction costs (NHK). A well-maintained Ytong house from the 1990s with recently modernized heating and insulation systems commands comparable prices on the market in suburban areas of Nuremberg to solid-construction houses built using other methods. Buyers purchasing such a property should know the year the blocks were manufactured as well as the original lambda value of the Ytong generation used-this information can often be found in old construction plans or at the building department and helps assess the actual need for renovation. Newer Ytong houses from generations dating from around 2005 onward, featuring PP2 blocks and wall thicknesses of at least 36.5 cm, are generally GEG-compliant and achieve energy efficiency ratings ranging from B to A.

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