Damp and mould – why blame landlords?

Many new homes in New Zealand, despite adhering to the Building Code, still face issues with dampness and mould. This problem stems from fundamental inadequacies in the current Building Code requirements for managing indoor environments and an overly simplistic method for assessing and minimizing condensation and mould growth on internal surfaces. The core of the issue lies in Acceptable Solution E3/AS1, which is the method used to assess moisture on the internal surfaces of timber-framed walls and roofs. This solution fails to account for the impact of thermal bridges on surface temperature, thereby not reliably preventing condensation and mould. Thermal bridges are created when building materials like timber studs bypass insulation, allowing heat to transfer more readily. Since timber is a less effective insulator, an increase in thermal bridges directly correlates with a greater influence on surface temperatures and, consequently, a higher risk of condensation and mould. The Building Code's current approach relies on an R-value of R-1.5, calculated using the 'isothermal planes' method. This method averages the thermal resistance of timber studs and insulation, overlooking the localized effects of timber on surface temperatures and assuming one-dimensional heat flow. This assumption neglects heat loss occurring in multiple directions at timber junctions. Compounding this, modern homes often incorporate significantly more timber framing than assumed by designers, exacerbating the problem of thermal bridging and potentially leading to subpar thermal performance, increased surface condensation, mould growth, and unhealthy living conditions. Addressing these challenges necessitates a more sophisticated approach to assessing building performance. Research indicates a direct relationship between the complexity of assessment tools and the reliability of results. While highly detailed tools offer the most accurate insights, they also come with higher costs and time commitments. A PhD research study compared Building Component Simulations (BCS) and Whole Building Simulations (WBS) to identify an optimal balance between detail and practicality. BCS models specific building components or junctions, like thermal bridges, while WBS can calculate a home’s entire internal climate, factoring in variables such as building orientation, construction materials, conditioning systems, and ventilation. The research confirmed that while reducing thermal bridging and increasing insulation are beneficial, they alone cannot entirely eliminate the risk of condensation and mould. Other variables, including heating and ventilation, are crucial considerations. The findings suggest that assessing moisture risk using a whole building simulation, which calculates internal temperature and relative humidity, is more effective than focusing solely on individual components. Whole building simulations require comprehensive data, including the building's geometry, material properties, and detailed information about ventilation, heating, cooling systems, and occupant behavior. Initiatives like the Housing Energy End-use Project 2 by BRANZ are vital in providing the necessary data on housing stock, construction methods, and typical occupant usage patterns. Adopting a whole building approach for risk assessment could not only ensure compliance with the Building Code's internal moisture and energy efficiency standards but also help mitigate the growing issue of overheating, particularly in apartments. This holistic modeling approach would enable designers to improve occupant health, thermal comfort, and energy efficiency through strategies like enhanced insulation, modeled from the initial design phase, leading to better outcomes than merely meeting minimum Building Code requirements and potentially reducing costs. #NewZealandHomes #BuildingCode #Dampness #MouldGrowth #ThermalBridging #WholeBuildingSimulation #HomeDesign #IndoorEnvironmentQuality #EnergyEfficiency

Mould and damp are common household issues that can lead to unpleasant aesthetics and potential health hazards. These problems often escalate during periods of high humidity, particularly following wet seasons or in environments with reduced airflow. Understanding the conditions that foster mould growth and implementing preventative measures are crucial for maintaining a healthy home environment. Mould thrives on organic matter, such as dust, dead skin cells, and pet dander, which emphasizes the importance of regular cleaning. Prevention is the most effective strategy against mould and damp. This involves minimizing moisture entry into the home by regularly checking for and repairing broken tiles, roof leaks, and ensuring gutters and downpipes are clear. External windows and doors should be assessed for proper sealing, and weather seals installed if necessary. Good ventilation is paramount; opening windows to air out the house and keeping air flowing helps to reduce humidity. Drying clothes indoors should be avoided as it significantly increases indoor humidity. If indoor drying is unavoidable, using a heat pump condenser clothes dryer, which collects moisture in a reservoir rather than releasing humid air into the room, is recommended. Alternatively, a vented dryer with an external venting kit can redirect humid air outdoors. Installing exhaust fans in bathrooms and laundries is also beneficial for humidity control. Thoughtful heating and cooling practices, such as avoiding unflued gas heaters that release moisture and moderating air conditioning settings, can also prevent condensation. Various appliances can aid in managing mould and damp. Dehumidifiers are particularly effective for persistent damp problems, especially in rental properties where renovations are not an option, or after minor leaks or floods. They remove moisture from the air, thereby preventing mould. There are two main types: refrigerant dehumidifiers for hot, humid conditions and desiccant dehumidifiers for cold, damp conditions. While models vary in price, effectiveness does not always correlate with cost, with expert reviews showing that many effective models cost $500 or more, and some cheaper models performing poorly. Air conditioners, commonly used for temperature control, also possess dehumidifying properties, and many modern units include specific 'dry' modes designed for this purpose. Ceiling fans are an energy-efficient way to maintain airflow and prevent mould. They can also be used in winter to circulate warm air, making heaters more efficient. Pedestal fans offer a more portable and inexpensive solution for directing airflow to specific areas requiring ventilation. When mould appears, immediate and appropriate cleaning is necessary. Many commercial 'mould-killing' products contain insufficient bleach concentrations (often 5% or less) to effectively kill fungi, which typically requires a 10% bleach concentration. Moreover, bleach loses potency quickly. Instead, a standard multipurpose cleaner or a mixture of 80% vinegar and 20% water with a microfibre cloth can be effective. Vinegar causes mould to overeat and die. However, for serious mould problems or mould on highly porous materials like textiles, clothing, or furniture, complete removal might be impossible, necessitating disposal of the affected item. Similarly, mould in bathroom grout may require regrouting. Professional mould remediation is advisable for dense, black mould covering significant areas, as it can be expensive but prevents further damage and identifies underlying causes. For renters, landlords are generally responsible for mould caused by structural issues like leaks, but clear-cut laws regarding landlord responsibility for mould are often lacking. Renters should document the issue with photos and maintain records of all communication with landlords or real estate agents. #HomeMaintenance #MouldPrevention #DampControl #Dehumidifiers #AirConditioners #CeilingFans #HomeVentilation #CleaningTips #RentalRights

Mike Parrett FRICS, a self-described building pathologist, has dedicated over four decades to understanding the causes of building failure, particularly focusing on damp. His expertise, spanning from South London housing estates to historical landmarks like Saint Mark's Basilica, emphasizes the need for a comprehensive approach to diagnosing and preventing damp, moving beyond superficial fixes. Parrett challenges the conventional practice where surveyors refer property owners to commercial damp-proofing companies, which often leads to misdiagnosis, unnecessary expenditure, and recurring problems. He advocates for an independent investigation into the underlying causes of damp, similar to a medical doctor's role in diagnosing illness. Parrett's early career in social housing repair and maintenance revealed that damp and mould were the most frequent complaints and often detrimental to tenants' health. He observed that the common practice of chemical damp-proof injections and waterproof plaster retrofits often failed because they did not address the true causes of damp. At Lewisham Council, he successfully implemented a policy to halt chemical damp proofing, saving millions and allowing for more effective solutions. He asserts that in his 40 years as a consultant, he has never recommended chemical damp-proof course injections. The article highlights various contributors to damp and mould, including defective guttering, blocked cavity wall voids, leaking water mains, faulty plumbing, and blocked air vents. Underheating, exacerbated by rising energy prices, is identified as a growing national problem contributing to damp. Climate change is also noted for its role in raising water tables, impacting even historic properties previously unaffected by damp. Parrett's work at Saint Mark's Basilica exemplifies addressing complex damp issues in historic structures, where a specially developed acrylic paste was used, prioritizing solutions that are reversible and preserve the building's integrity. Parrett criticizes the current retrofit agenda aimed at increasing energy efficiency, arguing that it often traps moisture within old buildings not designed to be hermetically sealed, leading to warm, humid homes rather than warm, dry ones. He suggests that internal insulation might sometimes be more effective than external applications, but policymakers are often deterred by cost. The article also touches upon the dangers of inappropriate external cladding and cavity wall insulation, drawing parallels to disasters like the Grenfell Tower fire and Champlain Towers collapse. He proposes that lessons from such failures should be integrated into building information modeling (BIM) to inform future design and maintenance. Parrett concludes that building failure is not limited to aging structures; poor design and construction are endemic in new buildings globally. He argues for a shift in the surveying industry, advocating for the training of specialized building pathology experts who can conduct independent investigations and collaborate in multidisciplinary teams. This approach would ensure that issues are designed out from the outset and that proper, unbiased diagnoses are made when buildings fail, moving away from commercial interests. #BuildingPathology #DampPrevention #BuildingFailure #HistoricBuildings #RetrofitChallenges #ClimateChangeImpact #BuildingDesign #SurveyingIndustry

A leasehold flat owner, Gordon, seeks advice regarding a significant damp problem discovered in his property, purchased the previous December. The problem, which he didn't detect during inspection due to obstructed areas, emerged shortly after moving in. He attributes not having a proper survey done to being in a state of grief at the time of purchase. His solicitor was unhelpful, mistakenly believing the property was freehold, despite the flat being built in the 1920s and a known history of similar damp structural issues in the street, with at least six properties requiring remedial work in the past five years. His adjoining neighbor had repairs for the same structural issue five years prior, but the freeholder denies any interconnection between the two flats, despite being built on the same base. Gordon recently received a Section 20 notice, which he disputes, concerning the remediation of the damp. Community members offer various suggestions. Darren Peters advises Gordon to obtain an independent structural surveyor's report to properly assess the problem and its remedies, which would provide stronger evidence in any dispute with the freeholder. He also asks for clarification on the purpose of the Section 20 notice. Tim Rogers identifies two core issues: the cause of the damp and the responsibility for its repair. He explains that older properties, like Gordon's 1920s flat, often have solid wall construction with a slate damp proof course that can crack over time, leading to rising damp. He describes two common solutions: 'tanking' walls with plastic sheets up to one meter or silicone injection, noting the latter's limited lifespan. Gordon clarifies that the freeholder's survey indicates a collapsed damp course membrane. The freeholder's proposed remediation involves extensive work: emptying the flat, storing contents, finding alternative accommodation at Gordon's expense, removing kitchen units, fireplace, skirting boards, concrete floors, and then installing new wooden flooring, hacking off a half-meter of plaster around the entire flat, and forming a new membrane, both internally and externally. This process is expected to take months. An environmental survey identified the problem as a Category 2 hazard. Gordon notes that his adjoining neighbor, who had a similar issue five years ago, was rehoused and had their belongings stored at the freeholder's expense, but his freeholder denies any link between their flats. Judith Wordsworth suggests that rectification works and alternative accommodation should be covered by the freeholder and/or the block building's insurance policy. She advises Gordon to review his copy of the block building's insurance policy for clauses regarding alternative accommodation and storage, as it is unlikely he should bear these costs for a structural building problem. She recommends contacting the insurer directly for confirmation. Gordon adds that the Section 20 notice is for "major qualifying works" related to the damp. He highlights that he was given an impossibly short deadline to submit his own survey and proposed works after receiving the freeholder's response. David (not Goliath) suggests exploring a claim against the previous owner for failing to disclose historical damp issues, which might have influenced Gordon's purchase decision or price negotiation. Gordon further reveals that his suspicions about the sale are strengthened by observations from his family and a questionable response from his solicitor regarding the previous tenant's habits, especially since both the vendor's and his solicitors were from the same firm, raising concerns about a conflict of interest and the quality of legal advice received during conveyancing. #DampStructuralIssues #LeaseholdFlat #Section20Notice #PropertyMaintenance #LandlordTenantLaw #StructuralSurvey #DampProofCourse #PropertyInsurance #ConveyancingIssues

A persistent musty smell in a basement often indicates underlying problems such as hidden moisture or mold, rather than being a normal characteristic of the space. Addressing this odor requires identifying its source, resolving the root cause, and then freshening the environment. Experts highlight that basements are prone to musty odors due to various factors, including accumulated dust, dirt, and clutter, which can trap smells. Deep cleaning, decluttering, and removing or washing fabrics and upholstery can reduce odor sources. Placing activated charcoal or baking soda can also help absorb lingering smells. Other potential sources include old carpets, boxed clothes, unused upholstery, and dirty air or furnace filters. To combat these, cleaning and thoroughly drying affected materials, replacing water-damaged items, maintaining HVAC systems, and promptly fixing hidden leaks are crucial. Moisture is a significant contributor to musty odors because it creates a conducive environment for bacteria and fungi growth. These microorganisms, when breaking down organic materials, release microbial volatile organic compounds (MVOCs) that produce a distinct musty or earthy smell. Even concealed moisture within walls or under carpets can lead to this issue. To tackle moisture, implementing several strategies is essential: utilizing a dehumidifier to remove airborne moisture, investing in a smart thermostat to monitor humidity levels, and immediately cleaning up spills or pooled water to prevent increased humidity and mold growth. Regularly inspecting and repairing leaks in pipes, water heaters, and basement walls is also vital. Ensuring that doors and windows are properly sealed prevents outdoor humidity and rainwater infiltration, while keeping them closed during rainy weather helps maintain stable indoor moisture levels. Maintaining clean gutters is important to direct water away from the foundation, and proper insulation helps regulate temperature and reduce moisture buildup. Improving air circulation with fans, open doors, and clear vents prevents trapped humidity, and reducing carpeting in favor of hard flooring materials like tile or vinyl minimizes moisture retention. Storing items in airtight plastic bins instead of absorbent cardboard boxes or fabric also helps prevent dampness and contamination. Mildew, which is an early stage of mold, grows rapidly in moist, organic environments. It serves as a warning sign before a more severe mold infestation. While bleach water or proper mold cleaner can address mildew on hard surfaces, its recurrence indicates an unresolved humidity problem. To effectively combat mildew and mold, it's recommended to use cleaning products that eliminate particles without compromising indoor air quality, such as botanical products with surfactants, microfiber materials, and HEPA vacuums. Frequent and thorough cleaning of the entire indoor space, particularly dusting, helps reduce microscopic particles like mold spores and bacteria. Reducing clutter makes surfaces easier to clean, further minimizing contaminants. Washing porous materials like bath mats, towels, and bedding with botanical laundry additives is also advised. Scheduling biannual HVAC professional servicing ensures the system is free of contamination and functioning correctly. Investing in air purification technology that removes the smallest particles and upgrading to high-rated MERV filters, changed regularly, can significantly improve indoor air quality. Additionally, proper maintenance of houseplants, including avoiding overwatering and clearing debris, helps prevent mold growth. Poor airflow contributes to musty odors by allowing moisture and stale air to become trapped, fostering the growth of mold, mildew, and bacteria. The resulting release of gases by these microorganisms produces the unpleasant smell. Increasing ventilation by opening windows when dry, using oscillating fans, and keeping interior doors open can improve air circulation. Regularly clearing air vents and filters ensures fresh air circulates effectively. When a musty smell persists or visible mold is present, professional intervention is necessary. Visible mold often indicates a larger, hidden problem behind walls, under flooring, or in other concealed areas. DIY mold testing kits are often unreliable, making professional mold inspection crucial for accurately assessing the situation, identifying the mold's location and the moisture source, and formulating a remediation plan. Professionals use tools like moisture meters and thermal imaging to detect hidden issues such as foundation leaks, poor drainage, high humidity, or leaky pipes. Addressing a musty basement smell is not just about comfort but also about mitigating potential health hazards associated with mold. #MustySmell #BasementMoisture #MoldRemediation #HumidityControl #AirQuality #HomeMaintenance #CleaningTips #Ventilation #ProfessionalInspection

The article addresses a common problem faced by tenants: a landlord's repeated failure to adequately fix a recurring leak in an apartment. The problem centers on a pipe leak between floors, which has been 'fixed' multiple times by a building repairman, likely not a licensed plumber, using only caulk. This superficial repair consistently fails, leading to water damage and personal item destruction, and raises questions about a tenant's recourse. According to attorney Sam Himmelstein, the initial and most crucial step for a tenant in such a situation is to establish a comprehensive paper trail. This involves documenting all communications with the landlord in writing, ensuring that these communications can be proven to have been received. Acceptable methods include email, faxes, certified mail, messenger services, or FedEx. This documentation serves two primary purposes: first, it signals to the landlord the tenant's seriousness about the issue, often prompting more effective action due to the landlord's apprehension about written records being used in legal proceedings. Second, it provides concrete evidence that the landlord was aware of the problem but failed to address it properly, which is invaluable if the situation escalates to court. If written communications do not resolve the issue, a tenant has further options. One avenue is to contact 311 to request an HPD (Housing Preservation and Development) inspector. However, this approach has a timing constraint; an inspector would need to be present when the leak is actively occurring to observe and document the problem, which can be challenging to coordinate. A more effective and reliable course of action suggested is to file an HP (Housing Part) action in Housing Court. An HP action can lead to a court order compelling the landlord to perform the necessary repairs. If the landlord fails to comply with this order, they could face fines and even be held in contempt of court. Throughout this process, the tenant should diligently gather and preserve evidence. This includes taking dated and timed photographs of the leak, the resulting damage, and any inadequate repairs. Such visual evidence, combined with the written communication log, strengthens the tenant's case by providing verifiable proof of the ongoing issue and the landlord's inaction. This advice is critical for tenants dealing with negligent landlords, offering practical steps to protect their rights and ensure their living conditions are maintained. #TenantRights #LandlordResponsibility #BathroomLeak #NYCRealEstate #HousingCourt #PropertyMaintenance #RentalIssues #LegalAdvice #TenantAdvocacy

During the peak of the U.S. housing boom in 2005, over two million new homes were constructed, a stark contrast to the half-million started in 2009. This rapid expansion, fueled by rising home prices and loose mortgage terms, led developers to prioritize speed and cost-cutting, often compromising construction quality. This frenetic pace resulted in significant issues, as an estimated 17 percent of homes built in 2005 have at least two major defects, ranging from structural failures to leaky roofs. One common problem stemming from expedited construction is leaky roofs. A watertight roof involves precise pitch to direct water away from the house and the proper installation of waterproofing materials like metal flashing and felt underlayment. Rushed contractors often neglect these critical steps, leading to poor drainage, omitted flashing over vulnerable seams, or the absence of felt backing, all of which can cause water infiltration, costly damage, and mold growth. Another frequent issue is leaky windows. Proper window installation is a multi-step process requiring specialized skills and layered sealing materials. During the boom, a shortage of qualified workers and quality materials led contractors to cut corners. This included failing to apply rubberized flashing to the sides and top (head) of windows, or using inadequate foam insulation. While the bottom of a window frame is intentionally less sealed to allow drainage, improper sealing elsewhere leads to leaks, drafts, fogging, and moisture intrusion, which can saturate wooden components, bulge walls, and foster mold. Basement flooding is also a significant problem, often attributed to contractor negligence rather than natural causes. While no foundation is completely waterproof, effective design and materials can prevent water accumulation. Rushed contractors may not properly grade the property to direct water away from the foundation, fail to install gutters and downspouts to manage rainwater, or neglect to use free-draining backfill (like gravel) around foundation walls. This backfill is crucial for directing groundwater to a subterranean drainage system, preventing hydrostatic pressure buildup and subsequent flooding. Cracked foundations represent a severe structural flaw. An example from the Blue Oaks subdivision in California highlighted how builders neglected soil testing, leading to homes cracking due to expanding and contracting clay soil. In other cases, rushed construction involves inadequate rebar reinforcement in concrete foundations or insufficient tamping of fill soil beneath footers, causing continued settling and cracking. Finally, mold outbreaks are a particularly nasty consequence of fast-paced building. Mold thrives in moist environments, and builders operating under tight deadlines sometimes use damp plywood, sealing it before it can dry, or fail to properly insulate pipes, ventilate attics, or seal HVAC ducts. This creates ideal conditions for mold growth, which can produce mycotoxins harmful to health and spread allergens throughout the house, impacting residents' well-being. #ConstructionDefects #HousingBoom #HomeMaintenance #BuildingQuality #PropertyIssues #MoldOutbreaks #FoundationProblems #WaterDamage