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.
