Mycotoxins are secondary metabolites produced by various types of mold or bacteria. These toxins can cause a range of health problems, including immune system weakening, neurological disorders, allergic reactions, and even cancer. For building biologists, particularly important are the types of mold that produce mycotoxins and grow indoors. The most common types include Aspergillus, Penicillium, Stachybotrys, and Cladosporium.
Continue reading
Avoid noise from heatpump outdoor
The Bavarian State Office for the Environment (LfU) has published a guide to dealing with noise problems caused by the installation of air-source heat pumps in private houses. In this connection the authority examined individual components of a heat pump regarding noise. Fans are not the only source of noise, but they are responsible for ninety percent of noise problems. During the preparation of the guide, it also came to light that there are considerable differences in the quality of individual products in terms of noise. After all, if all components of an air-source heat pump are optimized in terms of noise, the sound power level should be no more than 50 dB(A). In fact, however, the sound level of equipment on the market can be 70 dB(A) and above.
Continue reading
formaldehyde in an office
Six months ago Anne Hopf took up her new job in a public authority in North-Hesse/Germany. She is sitting in an office space of twenty square meters, together with a colleague. In the room are built-in wardrobes, shelves and many about seventy well-stocked folder. Four weeks ago Anne Hopf complains often of headaches and burning eyes. The colleague of Anne, however, has no complaints. The supervisor has addressed the matter and commissioned a building biologists for root cause analysis. Based on the described symptoms and the existing spatial features, the expert suggests an air sample in formaldehyde.
Continue reading
Marlene Sandner (Germany) wanted to replace the worn wooden floor in her old apartment in the city center with a new parquet floor. To her surprise, demolition work revealed a smelly old linoleum floor underneath the floorboards, which was obviously glued to the screed. The adhesive was already crumbling and showing signs of dissolution. After the linoleum was removed, remnants of the adhesive remained stuck to the screed. The flooring installer suggested sealing the surface twice with epoxy resin and smoothing out any remaining unevenness with a leveling compound. The new parquet was then to be laid on top. Marlene Sandner is still hesitant and is therefore seeking advice from the environmental consultancy.
Continue reading
Avoiding alternating electric fields at the sleeping place
Sabine Loderer from Ansbach in Bavaria/Germany moved into a new bedroom within the house. Fittingly, the couple had purchased a new double bed in June. The selected model has a reading lamp integrated on the left and right side of the headboard. Sabine Loderer has been sensitive to electrosmog for several years and therefore had a mains decoupler installed in the circuit of the old bedroom. This device interrupts the power supply when the last “consumer” has been disconnected from the mains. In the new bedroom, this protective device was still missing. In recent weeks, Mrs. Loderer noticed that she was sleeping increasingly poorly. She wanted to get to the bottom of the cause and commissioned the building biologist Oliver Zenkel to conduct a sleeping place investigation.
Continue reading
Hardly any component in a building has made such rapid progress in the field of thermal insulation as the window. Within twenty years, the U-value has improved from 2.6 to less than 1.0. The industry has made many adjustments, optimizing each window element individually. Triple glazing is now standard for a highly insulated house. This is complemented by integrated insulating inserts made of extruded polystyrene (XPS) or cork in the window frame, inert gas fillings in the spaces between the panes and thermally optimized edge seals.
Continue reading
Floor identified as source of pollutants
When looking for the source of pollutants in the indoor air, Oliver Zenkel always focuses on the floor first. The building biologist draws on several years of experience and also provides a simple reason. Although walls have the larger surface portion at a dwelling, but floors are usually multi-layered developed and thus substantially more susceptible for pollutant entries into the ambient air. Zenkel views flooring as a system in which not only the individual material plays a role, but also the interaction of the components.
Continue reading
Mold grew nearly overnight – Sylvia Bittner couldn’t believe her eyes when she moved the bed in the children’s room to one side. Within two weeks, a dark turf of mold had grown on the wallpaper from the base to a height of forty centimeters. Sylvia had only moved into the rented apartment on the second floor with her family in the summer. The realtor had told her nothing about a mold problem and the apartment had been freshly painted. In late November, mold growth came upon the residents out of the blue. Sylvia picked up the phone and reported the matter to the property manager. When after eight days there was still no remedy in sight, the worried mother of two asked the consumer advice center. The friendly lady on the phone advised her to record the damage with a camera and to put the property management in default in writing. The advicer recommended that the rent payment be made with reservations so that she could later assert claims for repayment. But Sylvia Bittner was not thinking about money at first – she was much more concerned about the health of her children.
Continue reading
Seven low-level mobile phone antennas are located along the shore road in the Skeppsbron district of Stockholm (Sweden). An international team of researchers led by Mikko Ahonen from Finland and Michael Carlberg from Sweden concluded in a study that the determination of the locations along the shore road serves as an example of a poorly designed antenna structure. A portable exposimeter was used to record electromagnetic radiation at various measurement points. The highest average field strength in one of the defined segments was 12.1 volts per meter (V/m), corresponding to a radiation density of 388 milliwatts per square meter (mW/m²). The peak value in the area studied was 31.5 V/m (2,648 mW/m²), reaching over 50 percent of the internationally accepted limit of 61 V/m at a frequency of 2,600 megahertz.
Continue reading
Architect Florian Hoppe presents the straw bale building