Designing for deconstruction (DfD)

Question 1

What is the general concept of Deconstruction?

Answer 1

Disassembly of building to reuse/recycle components
A predemolition ordit is completed assessing what is in the building

Question 2

Advantages of Deconstruction

Answer 2

1. Less heavy equipment
2. Lower equipment costs
3. Avoids disposal & landfill costs
4. Preservation of the environment (less pollution)
5. Provides builders with cheaper materials
6. Cost-effective alternative to demolition

Question 3

Disadvantages of Deconstruction

Answer 3

1. Costly
2. Time consuming (2-3 weeks compared to days)
3. Not all buildings are suitable
4. May encounter hazardous materials
5. Materials might be too ‘dated’

Question 4

What is unavoidable and avoidable waste?

Answer 4

Un - costs to reduce waste are higher than the economy produced

Avoidable - when necessary investment to manage the waste is higher than the costs to prevent or reduce it

Question 5

Drivers for change

Answer 5

Environmental drivers (materials not used, waste goes to landfill without reuse, skipped materials)

Financial drivers (Landfill/disposal costs)

Government policies and regulations (Resources & waste strategy for england, Landfill tax)

Question 6

Routemap for 0 waste in construction

Answer 6

Design for end of life
Design out waste
Encourage refurbishment over demolition
Exploit off site manufacture
Reduce waste from temporary works
Analyse and report waste to landfill
Report on waste at project and company level

Question 7

Origins of construction waste

Answer 7

Design (unclear specification, Design changes, late information)

Procurement (Ordering errors, suppliers errors)

Site operations (Poor workmanship, offcuts from cutting materials to length, improper planning for required quantities)

Material storage and handling (Improper storing methods, materials supplied in loose form, Inappropriate site storage space leading to damage or deterioration)

Question 8

Waste minimisation hierarchy

Answer 8

1. prevention
2. Preparing for re-use
3. Recycling
4. Other recovery
5. Disposal

Question 9

Barriers to construction waste

Answer 9

Accepted as inevitable
Lack of training
Poor defined individual responsibilities
Lack of interest from clients

Question 10

Integrated waste minimisation strategy

Answer 10

Reduction at source (waste management/policy, take-back policy in place, deconstruction)

Management of minimum waste generation (Reuse, recycle, recover)

Question 11

UK contractors doing for responsible sourcing

Answer 11

BUILD UK group of contractors show preference to suppliers who can demonstrate responsible sourcing

Question 12

Drivers for responsible sourcing

Answer 12

Reputation/brand
Competitive advantage
Attract and retain customers
Corporate responsibility
Reducing risk