Construction Technology - Level 3's

Question 1

On South Kensington, you prepared a Facade Presentation. What was the advice you gave to the Client in that presentation?

Answer 1

I advised the Client on typical cost ranges of residential facades. I included a bar chart to compare the £/m2 (Blended Facade Rate) against similar projects. This also advised the client on the relationship between £/m2 of facade against targeted sales values

By doing this exercise I was able to demonstrate to the Client that South Kensignton was on the higher end of the ranges and advised that VE could be implemented to improve the £/m2 against sales values

Question 2

What was the materiality of the South Kensington Facades?

Answer 2

Affordable:

• Reconstituted Stone
• Brick facing precast concrete with expressed columns
• Full height double glazing
• Aluminum Louvres
• Aluminum Cladding to top floor

Private:
Similar materiality but also had ‘hit & miss’ brickwork & Zinc Panels and expressed columns

Question 3

What was the most expensive material on the facade at South Kensinton?

Answer 3

Full height glazing - £1,200/m2
Brick facing precast concrete panels - £1,250/m2

Question 4

What was cost ranges for the different between affordable and private residential buildings?

Answer 4

Affordable - £600 to £1,400/m2
Private - £950 to £1,850/m2

Question 5

What is a Stick system facade?

Answer 5

Stick systems area cladding systems which are constructed on site.

Different elements or materials are delivered to site and the facade is installed piece by piece

Question 6

What is a Unitised facade?

Answer 6

Unitised systems are prefabricated off site and delivered and installed straight away as panels.

Question 7

How are Unitised facades installed?

Answer 7

They are typically lifted to location via a crane and installed from the inside of the floor plate

Question 8

What are advantages of a Unitised Facade?

Answer 8

Installation time is shorter than stick

Lower labour costs (as a result of faster installation)

High quality are fabricated and glazed in a climate controlled environment

Question 9

What are the disadvantages of a Unitised Facade?

Answer 9

On site installation is faster but fabrication & design time has to be factored in to overall programme

Not suitable for smaller projects due to lengthy fabrication time and cost

May require materials off site payments

Question 10

What are the advantages of a Stick Facade?

Answer 10

Can be more economical, particular for smaller projects

Lead in time is much shorter

Materials readily available allow for earlier installation

Question 11

What are the Disadvantages of a Stick Facade?

Answer 11

Installation on site is longer

Materials require space on site to be stored

Installed on site in unpredictable conditions (Weather)

Question 12

Can you summarize the advantages / disadvantages of untised and stick facade systems?

Answer 12

Unitised:
Time - quicker installation, longer lead in times
Quality - higher quality product (made in factory)
Cost - More economical for larger projects (economies of scale)

Stick:
Time - Quicker lead in time, longer installation on site
Quality - parts fabricated on site in unpredictable conditions, not as good as unitsed
Cost - More economical for smaller projects

Question 13

Why did you advise on a Unitised system for South Kensington?

Answer 13

Due to the scale of the project it could be more economical using unitised façade, there was lots of repetition on the buildings and would speed up the construction programme.

By using a unitised system a high quality product be guaranteed due to being made in factory conditions and not on site.

Question 14

What where the various frame options you advised on on Lydden Road?

Answer 14

Steel Frame with Composite metal deck

Steel Frame with CLT slab

RC Frame with PT slab

RC frame with CLT Slab

Question 15

What was your advice to the Client on the different frame options for Lydden Road

Answer 15

Frame options were ranked from most cost effective to least cost effective

Key metrics were identified including:
Design efficiencies
Net:gross
Pros & Cons of each option

Question 16

What was the most cost effective frame option for Lydden Road?

Answer 16

RC frame with PT Slab = £73/ft² on the GIA

£4.8m total cost

Question 17

What was the least cost effective frame solution for Lydden Road?

Answer 17

Steel Frame with CLT Slab hybrid = £96/ft² on the GIA

£6.4m total cost

Question 18

What were some of the pros and cons you advised on the frame costs for Lydden Road?

Answer 18

RC frame with PT Slabs
Pros - most cost efficient
Cons - Thicker slabs than composite deck and reduced floor to ceiling

Steel with Composite deck
Pros - Wider spans with uninterrupted floor plates improved the NIA, lighter frame could result in reduced foundation costs
Cons - Not as cost effective as RC frame and PT slab and prices of steel being volatile

CLT Slab solutions
Pros - Increased sustainability credentials
Cons - Bespoke, most expensive solution and limited supply chain. Deep floor build ups reducing floor to ceiling heights

Question 19

On Devonshire Row (D&B) why was the secondary set of fire doors a cost to the Client? Was it not the Contractors responsibility to ensure the building was compliant with building regulations?

Answer 19

The ER’s specified bespoke reeded glass entrance doors (it was not specified these doors has to be fire rated) Building control requested proof the doors were 60 min fire rated and they needed to be sent to a factory to gain the fire certification. This would have caused a delay to the programme so the Client agreed to introduce a secondary set of fire doors as a solution to main programme as a post contract client change.

Question 20

What was the cost of the secondary set of fire doors on Devonshire Row?

Answer 20

£11k - Doors were clad in mild steel and were connected to the fire alarm system. This included stripping out the existing wall linings and fire stopping.

Question 21

What was the building regulation which stipulated Fire Doors on Devonshire Row?

Answer 21

Approved Document B (fire safety) volume 2:

Buildings other than dwellings, 2019 edition incorporating 2020 amendments

Question 22

What is the purpose Approved Document B (fire safety)?

Answer 22

Approved Document B addresses fire safety precautions which must be adhered to, to ensure the safety of occupants, firefighters and those close to the building in the event of a fire.

It covers means:
Means of escape
Ability to isolate a blaze to prevent from spreading
Fire detection and warning systems
Materials used in a building prevent fires spreading

Question 23

Are you aware of any other legislation concerned with Fire regulations?

Answer 23

Approved Document B (Fire Safety)
Regulatory Reform (Fire Safety) Order 2005
The Fire Safety Act 2021

Question 24

What is the Fire Safety Act 2021?

Answer 24

Legislation post Grenfell introduced to clarify who if responsible for managing and reducing fire risks in multi-occupied residential buildings.

Puts new obligations to leaseholders, building owners and managers

Question 25

Is advising on fire requirements part of your role as a QS?

Answer 25

No and is not covered in our PI insurance.

I advised the client on the stipulations from building control and that a post contract client change instruction may be the best solution to maintain programme