Approved Document C Flashcards
What is Requirement C1?
C1 ensures that sites are prepared properly and buildings are resistant to contaminants and hazardous substances.
What contaminants must be considered in site preparation?
Radon, methane, carbon dioxide, sulfates, heavy metals, and asbestos.
What is the purpose of a site investigation?
To assess ground conditions, identify contamination risks, and ensure structural stability.
What are common sources of contamination in building sites?
Former industrial use, landfill sites, chemical spills, and naturally occurring contaminants.
What measures should be taken if contaminated land is identified?
Remediation methods such as soil replacement, barrier systems, and gas ventilation measures must be used.
What is radon gas, and why is it a concern in buildings?
Radon is a radioactive gas that can accumulate in buildings and pose serious health risks.
How is radon risk assessed?
Using radon maps, geological surveys, and in-situ measurement techniques.
What protective measures are used against radon in buildings?
Radon barriers, underfloor ventilation, and positive pressurisation systems.
How does methane contamination affect building design?
Methane can accumulate in voids, creating explosion risks; gas membranes and venting systems are required.
What is the role of gas-resistant membranes in contaminated sites?
They prevent hazardous gases like methane and radon from entering buildings.
How does soil contamination affect foundation design?
Certain chemicals, such as sulfates, can degrade concrete and require special-resistant materials.
What are the main requirements for site drainage?
Water must be drained efficiently to prevent flooding and subsidence.
What is a remediation strategy in site preparation?
A plan to remove or mitigate contamination risks before construction begins.
What regulations govern contaminated land assessment?
Environmental Protection Act 1990 and BS 8485 for ground gas protection.
What is a vapor barrier, and how does it differ from a gas membrane?
A vapor barrier prevents moisture movement; a gas membrane prevents harmful gas ingress.
How can ground contamination impact groundwater?
Leachates from contaminated soil can pollute groundwater and affect water supplies.
What role does geotechnical assessment play in site preparation?
It assesses soil stability, contamination risks, and necessary foundation adaptations.
What are sustainable methods for remediating contaminated sites?
Bioremediation, chemical neutralisation, and containment using impermeable barriers.
What are brownfield sites, and how are they prepared for construction?
Previously developed land that requires contamination assessment and possible remediation before building.
How do tree roots affect site preparation?
Tree roots can cause soil shrinkage and heave, requiring foundation design adjustments.
What precautions should be taken for sites near old landfill areas?
Gas venting systems, impermeable barriers, and monitoring for hazardous gases.
How does topsoil quality affect site preparation?
Unsuitable topsoil must be removed or treated to ensure stable and uncontaminated foundations.
What legal responsibilities do developers have for site contamination?
They must comply with planning conditions, environmental laws, and ensure remediation before building starts.
What construction techniques can prevent contamination migration into buildings?
Sealed substructures, controlled drainage, and encapsulation of contaminated soils.
How does flood risk assessment relate to site preparation?
Flood-prone sites must incorporate flood resistance and resilience measures in building design.
What is Requirement C2?
C2 ensures that buildings are designed to prevent moisture penetration and damp-related issues.
What are the main sources of moisture that affect buildings?
Rain, groundwater, condensation, and leaks from plumbing systems.
What is rising damp?
Moisture that moves upward through porous materials due to capillary action.
How is rising damp prevented in buildings?
By using damp-proof courses (DPC) and damp-proof membranes (DPM).
What is a damp-proof course (DPC)?
A barrier layer, usually made of bitumen or plastic, installed in walls to block rising moisture.
What is a damp-proof membrane (DPM)?
A plastic or bituminous sheet placed under concrete floors to prevent ground moisture ingress.
How does external wall construction impact moisture resistance?
Cavity walls and waterproof render help prevent rain penetration.
What is the purpose of a cavity wall?
To provide an air gap that prevents moisture from passing from the outer to inner wall.
What are weep holes, and why are they important?
Small openings in cavity walls that allow trapped water to drain out.
What are the key design considerations for basements to resist moisture?
Basements must have waterproof membranes, drainage channels, and tanking systems.
What is tanking in waterproofing?
A method of sealing walls and floors using a continuous waterproof barrier.
How does groundwater affect foundation moisture protection?
Proper drainage and waterproofing must be installed to prevent water ingress from saturated soils.
What are the main methods for controlling condensation in buildings?
Ventilation, insulation, and moisture barriers.
How does ventilation help reduce condensation risk?
By removing excess moisture from the air, preventing surface condensation.
What is interstitial condensation?
Moisture that forms within walls or roofs when warm air penetrates and cools inside the structure.
How can insulation help prevent condensation?
By keeping surfaces warm and reducing the likelihood of moisture condensing.
What roofing features help resist moisture ingress?
Breathable membranes, proper drainage slopes, and flashing around joints.
What is the function of flashing in moisture protection?
Thin metal or plastic sheets that direct water away from vulnerable areas like windows and roof joints.
What precautions should be taken for timber structures regarding moisture?
Timber should be treated, ventilated, and separated from direct ground contact.
How does site drainage impact moisture control?
Proper drainage prevents standing water that could seep into walls and foundations.
What are the regulations for moisture-resistant construction in high-rainfall areas?
Buildings in these areas must have enhanced damp-proofing and cavity drainage systems.
What is flood resilience in building design?
The ability of a building to withstand and recover from flooding with minimal damage.
What materials are recommended for moisture-resistant finishes?
Render, water-resistant paints, and cement-based plasters.
How does water penetration testing ensure compliance with moisture resistance standards?
It verifies that walls, windows, and roofs can prevent water ingress under simulated weather conditions.
What are the key considerations for waterproofing balconies and terraces?
Proper drainage slopes, waterproof membranes, and sealants should be used.
