Construction Tech Flashcards
What are the advantages of a steel frame?
1) Beams span over long distances
2) High strength to weight ratio
3) Recyclable
4) Quick to erect on site
What are the disadvantages of steel?
1) The price of steel can be volatile.
2) Fire protection may be required.
3) Steel frames have lesser acoustic and thermal properties than concrete frames.
What can affect the cost of a steel frame?
1) Number of connections to beams
2) Making the steel fire resistant, with intumescent or boarding it.
3) Improving the acoustic qualities
How can you improve the acoustic qualities of a steel frame?
1) Whilst it might not improve the frame itself, I am aware of being able to install acoustic suspended ceilings to increase the acoustic performance of a building.
2) Insulation in ceilings and walls.
What are the advantages of a concrete frame?
1) The price of concrete is typically more stable than steel.
2) Fire protection is inherent in the structure
3) Provides good sound and heat insulation.
What are the disadvantages of a concrete frame?
1) Takes longer to install on site than steel & timber
2) For concrete’s maximum strength, can take up to 28 days for concrete to cure.
3) Concrete does not span as well as steel.
On the project in Chigwell, why was a timber frame not identified as an option?
I posed this question to my Client, however my Client had issues previously with obtaining insurance on a block of flats and was unwilling to take the risk.
What are the advantages of a timber frame?
1) Sustainable benefits
2) Construction on-site faster than concrete.
3) Structure is relatively lightweight
What are the disadvantages of a timber frame?
1) Can be difficult to get insured
2) Fire protection may be required
3) Potential for wet rot / dry rot
What was the cost difference between the steel frame and concrete frame?
For a two storey, circa 10,000ft2 GIA in Q3 2024, I anticipated costs of £280m2 for a concrete frame.
For a steel frame, I would anticipate costs to be around £200/m2 Q3 2024.
What fire resistance did you allow for on the steel frame?
Double boarding of 30-minute PIR boards.
What other factors did you consider for the steel frame?
I assumed a prelims saving of 6 weeks at £6,000 a week.
I also assumed there to be no impact to the GIA.
What was the overall cost of the project?
For the concrete frame:£4,000/m2.
For the steel frame:
£3,900/m2.
What is CAT A construction?
A very basic form of fit-out for a commercial building, typically only including elements necessary for occupation.
It is a blank canvas for interior and office designers, the next phase is Cat B.
What are the main components of concrete?
1) Cement
2) Aggregate
3) Water
What is reinforced concrete?
Concrete with reinforcements, usually steel bars, rods or mesh.
What should be considered when selecting the type of structural frame?
1) Programme requirements
2) Fire protection
3) Acoustic and thermal properties
4) Market conditions and supply cost
5) Site logistics and general constraints
What is Cat B construction?
CAT B fit out provides a space that is ready to move into and operate.
Can you tell me what a Principal Designer is, and where this role is defined?
The principle designer is a role listed under the CDM regs. The principal designer is the designer with control of the pre-construction phase.
This role is defined under the Building Regs (Building Safety Act)
For Chigwell house, why was a masonry construction not considered in your advice?
Masonry construction (brick) formed the external wall. I advised on the choice of frame.
Can you run through some characteristics that would impact the cost of Steel/concrete frames?
1) Whether it is made on/off site.
2) Reinforcement to concrete
3) Number of connections for steel.
You advised that the cables could be installed high level rather than in a trench. Is this not outside your PI? Especially since it seems that way forward would never have worked.
I advised on the opportunities that could result in a cost saving and brought this to the attention to the design team.
I did not advise the design team to change their design, I advised them that there would be a cost saving by installing the cables at high level rather than in the trenches, it was for the design team to assess if this was feasible.
For the trench, why did it need to be fully opened? Why were the cables not just pulled through?
There was asbestos in the trench that had to be removed.
This also meant that the cables were contaminated, and had to be cleaned and double bagged once removed and couldn’t be pulled through.
On project infrastructure, how did your knowledge of construction tech help with your assessment of labour requirements for the temp flooring?
I was able to break down each element of construction and allocate estimated time frames for the completion of the works to calculate the total duration of install.
Can you tell me the build-up of a stud partition
1) Top and base plate
2) Vertical studs
3) Insulation
4) Plasterboard
5) Pattressing if FCU’s are inside
What type of frame would you expect for a house?
Timber
What type of frame would you expect for a warehouse?
Steel portal frame
Who defines the meaning of Cat-A and B?
BCO - British Council for Offices
For your Leeds OCE, why were you doing a measure rather than another method? Is that in line with what NRM 1 says?
I was able to use benchmarked data to make assumptions on the different elements to give my Client more accurate cost data.
What is the difference between glu-lam and CLT?
The main difference is how they are oriented and used for in the building.
CLT:
- Layers are glued together at right angles to each other
- CLT is used for walls and floors
Glu-Lam
- Layers are glued together in the same direction, so timbers strength goes in one direction.
- Glu-lam used for load-bearing, such as beams, columns etc
Can you tell me 2 key pieces of construction tech regulation, and what they outline?
1) Building Regulations
2) Building Safety Act 2022
What are the Building Regs?
A set of approved documents detailing the requirements for a building with regards to different key elements, such as fire safety, structure, access into the building, maintenance, ventilation etc.
What is the Building Safety Act 2022?
It is a law that was introduced following the Grenfell fire to improve the safety of Buildings in the UK. One key piece of the Act was the need for Two or more staircases in buildings over 7 storeys in height or over 15m.
What buildings does the Building Safety Act 2022 apply too?
All buildings that are subject to Building regulations, with particular controls for high-risk residential buildings.
Do the Building Regulations apply to all buildings?
No - there are some buildings not subject to Building Regulations, such as temporary buildings (site accommodation) or extensions that are less than 30m2.
Regarding the PSUM flooring works, how were you able agreed a reduced value with the contractor when the item is provisional and note design or defined?
This was agreeing the final cost of the provisional sum once the scope had been defined. I liaised with other Contractors to break down the construction sequence and allocated time to each process. I held a face to face meeting to review this with the Contractor and took notes of the meeting. I agreed the costs and reiterated the discussions held in the meeting in writing.
On Chigwell, can you explain the advice regarding steel / concrete frame and why the client opted for concrete?
I advised on the advantages and disadvantages of both options, detailing the costs for both.
My Client proceeded with the concrete frame for it’s inherent fire resistant, thermal and acoustic qualities.
What other considerations did you account for when reviewing the different frame types?
Steel could create a better NIA due to concretes bulky structure.
I also considered the impact on foundations, as steel is lighter than concrete and could reduce volume of the concrete raft foundation. However, it would be for the design team / structural engineers to assess the impact on foundations.
What assumptions did you make when reviewing the costs for steel vs concrete?
I excluded adjustments to the foundations and assumed PIR boards to achieve a 60 minute fire rating to the steel. I also assumed rates based on benchmarked data from Q1 2025.
Did you factor in the time / prelims saving in installing steel vs concrete?
I adjusted the preliminaries on a week basis. I assumed concrete to take 11 weeks and steel to take 5 weeks to install, at £6k/week.
Can you tell me what type of frame is usually prefered for resi or hotel, and why?
Concrete - for it’s natural acoustic, thermal and fire resistance qualities.
What are you seeing in the market at the moment regarding steel prices?
In Q1 2025, the price per tonne was between £700 -£900 per tonne. Though recently, British Steel have noted their losses and are making cuts, which could impact the price of steel.
What is RIBA Stage 2?
Concept Design
What is RIBA Stage 0?
Strategic Definition
What is RIBA Stage 1?
Preparation and Brief
What is RIBA Stage 3?
Spatial Coordination
What is RIBA Stage 4?
Technical Design
What is RIBA Stage 5?
Construction and Manufacturing
What is RIBA Stage 6?
Handover
What is RIBA Stage 7?
Use
Can you tell me four things you would see in a CAT A scope, two of which being MEP items?
- Raised Access Flooring
- Lift fitout
MEP:
- Sanitary installations to communal areas
- Pipework & plumbing to communal areas
What are the Building Regulations?
A set of approved documents that set out the minimum requirements and standards for a building.
Can you tell me 3 sustainable construction methods you have experience of pricing, and how you did so?
Whilst I have not priced these items, I am aware of:
- Ground Source Heat Pumps
- Blue roofs
- Rainwater harvesting
What is an undefined provisional sum and how does this link to labour cost?
An undefined provisional sum is where there is not enough information at the point of signing the Contract for the Contractor to include into their programme, meaning they could be entitled to additional time & monies.
This links to labour because where the Contractor did not factor time into the programme for this element of work, they were entitled to additional labour.
What informed your view the labour here was high?
I liaised with subcontractor’s and researched the works to a detailed level so I could understand the overall scope. I reviewed the Contractor’s assessment of labour and couldn’t understand their assessment of the labour.
How do you go about advising a client on the matter of provisional sums?
Close them out as early as possible.
Was this project at post-contract stage? What do you need to be wary of when conducting sweeping design changes at post-contract stage?
- Programme implications
- knock-on affects to other elements of work, such as integration with services.
How did you price the panels changing to every 3 metres?
On a cost/m2 basis where I detailed
Are there any design implications that should be considered when changing from concrete to steel or vice versa?
- Integration with services
- Impact to NIA due to concretes bulky structure / additional columns.
Why did your Client proceed with concrete over steel despite this being the more expensive option?
Due to the natural fire resistance provided by concrete and the acoustic and thermal qualities.
What approved document means that you can’t have green walls on certain buildings?
B - Fire Safety.
(Combustible material).
What grade of concrete might you see on a concrete frame?
C25 and up?
What type of frame is used on a warehouse?
Steel Portal Frame.
What type of steel frame is used on a high rise?
Steel skeleton frame.
When was the RIBA plan of work issued?
2020.
On PwC Leeds, if it was an OCE, why was you measuring?
Because I had the information available, so I utilised it and made assumptions on the floor plans provided to give my Client more accurate cost data.
How did you report where you allowed for different types of walls / partitions?
I stated this within my assumptions and clarifications.
I also reviewed my allowances and assumptions with the design team.
What assumptions did you make on the partitions?
I assumed 30db glazed partitions to one side of the meeting room and 60db stud wall partitions in-between as a separating wall, and acoustic suspended ceilings.
On Priority Works, why was the fact the prov sum was undefined mean that labour was a large part of the cost?
The prov sum was undefined, meaning the Contractor was not able to include for the works within their programme. This meant that the Contractor was entitled to additional labour for this work.
On Project Infrastructure, what knowledge of construction technology did you use?
I liaised with the Contractor and other subcontractors to understand the construction process to install the temporary flooring.
I broke down each sequence of work and allocated time to each stage of construction to reach an overall assessment of the labour, which was less than the Contractor had applied for.
On Project Infrastructure, why did you conclude that Value Engineering was the best way to proceed?
Because Value Engineering aims at improving cost whilst maintaining quality and function.
I considered scope reduction, but the nature of this project was to keep the building live, and an omission of scope could compromise this.
I also didn’t wish to tell the Client to seek additional funding before seeking if there were cost improvements available.
Did you not consider other access panels instead of GRP for VE alternatives?
I considered trench covers and wooden boards, but the Client considered these to be insufficient in quality for the project and were rejected.
Why was the value engineering option of changing the floor finishes not considered from the get go if value management happens throughout the lifespan of the project?
Firstly, I was only involved in the project post contract.
Furthermore, VE was not considered pre-contract because the Client’s priority was to get into contract as early as possible.
Why did the Client proceed with the concrete frame despite your advice recommending the steel frame being the cheaper alternative?
The Client consulted the design team who advised the benefits of concrete outweighed the cost reduction from steel.
