Design and Specification

Question 1

Holy Name - How/why did you specify the concrete slab?

Answer 1

Specified by using NHBC guidance and confirmed by the in-house structural engineer. A252 mesh reinforcement, 150mm RC28/35 concrete cover. Garage exceeded over 16m2 so needed to be reinforced.

Question 2

Holy Name - How did you establish the client’s brief and determine their requirements for the project?

Answer 2

Verbal briefing, discussed clients requirements on site. Level of quality was fit for purpose.

Question 3

Holy Name - Why was the traditional procurement route chosen for this project, and what are its advantages?

Answer 3

Design was separate from construction, More control of quality, cost and design. Lump sum contract. Full design by the client.

Question 4

Holy Name - What was the purpose of producing pre-construction information, and how did it contribute to the tender process?

Answer 4

Provide existing H&S information, details the project, planning and management. Enables the contractor to assess resources needed to perform their duties under CDM 2015. Identify risks.

Pre Construction Information – Is a requirement of the CDM Regs 2015, Should be clear, concise and easily understandable. Identify risk, manage risk and remove risk if possible.

Question 5

Holy Name - How did you ensure compliance with building regulations throughout the design process?

Answer 5

Used the approved documents to comply and used an approved inspector.

Question 6

Holy Name - How did you determine the appropriate dimensions and specifications for the truss cut roof using TRADA span tables?

Answer 6

Weight of the tiles, pitch of the roof, height of the ridge and dimensions of the perimeter walls determined the structural timbers.

Question 7

Holy Name - How did you ensure that the design of the cut roof met the structural requirements and load-bearing capacity for the project?

Answer 7

Tile specification and in-house structural engineer approval.

Question 8

Prescot Primary - Which British Standard did you refer to?

Answer 8

BS 5250:2021 Management of Moisture in Buildings

Upstand Heights:- Upstands should conform to the recommendations of BS 6229:2018: Flat roofs with
continuously supported coverings – Code of practice: Section 7.1 concerning the minimum height of
upstands.
“The design of drainage falls should ensure that the continuity of the waterproof covering is maintained for
a vertical height of 150mm above the finished roof level at all abutments, door openings and parapets. For
inverted roofs, those overlaid with paving, or garden roofs, the finished roof surface is the upper surface of
the ballast, paving slabs or growing medium.”

The design of roof drainage should be carried out in accordance with BS EN 12056-3:2000 which
specifically states the following:
“All flat roofs should be laid to a minimum finished fall of 1:80, and to achieve this a design fall of 1:40
should be used to ensure proper drainage as recommended in BS 6229:2018.”

Question 9

Prescot Primary - How did you ensure that the selected roofing system met or exceeded the necessary regulatory and performance requirements?

Answer 9

U-Values. All in compliance with the current building regulations/0.18 U value. Conform to BS standards for the type of roofing.

Question 10

Prescot Primary - What criteria did you use to cross-check the design against British Standards and Building Regulations?

Answer 10

Unfortunately I didn’t have access to the BS publications but I did have access to the quotation in the Sika specification. I completed an internet search to ensure they BS numbers were correct. I checked the U-Values in the Building Regs.

Question 11

Prescot Primary - What were the advantages of the chosen roofing system compared to a traditional felt roof?

Answer 11

Due to the many roof protrusions and plant the liquid applied system was chosen. No hot works required.

Question 12

Prescot Primary - Did you recommend an IBG?

Answer 12

Insurance backed guarantee not recommended as the council take ownership of this risk.

Question 13

Sacred Heart - What did you do with their risk assessments?

Answer 13

The Designers Risk registers used to create a single document where all significant design risks can be identified, collated, monitored and ultimately reduced as part of the design process. As significant hazards were identified they will be added to the risk register and the relevant actions taken to reduce or eliminate the associated risks will be recorded.

As each significant hazard is reduced to its lowest practicable level, the remaining hazard and any identified control measures will be logged and subsequently communicated to Contractors via the Pre-Construction Health and Safety Information and to the end user by the Health and Safety File.

Question 14

Sacred Heart - What were the key considerations when advising your client on re-building a boundary wall?

Answer 14

Party Wall Etc. Act 1996.
Party Structure Notice
Three/Six Metre Notice
Line of Junction Notice

Question 15

Sacred Heart - How did your role as Principal Designer contribute to the overall success and safety of the boundary wall re-build project?

Answer 15

Single point of contract for reducing health and safety risk, communication with all stakeholders.

Question 16

What are preliminaries?

Answer 16

Preliminaries (or ‘prelims’) are part of the design/tender documents prepared by the Building Surveyor on behalf of the client. Preliminaries provide a description of the project that allows the contractor to assess costs which, whilst they do not form a part of any package of works, are required by the method and circumstances of the works

Question 17

Difference between preliminaries and preambles

Answer 17

A preamble is an explanation of a document, commonly found in contracts, specifications and bills of quantities. It can help with the interpretation of the document. A preamble might include, a description of the parties to the contract, the background to the document, the objectives of the project, and so on.

Question 18

What are materials and workmanship?

Answer 18

This is the part of a Specification of Works that details the method of working, what the benchmark or the quality standard required is and highlights matters that will affect the workmanship. This part of the specification may include manufacturers’ product guidance notes and methods of application and/or may refer to guidelines for working established by the Building Research Establishment (BRE) or a relevant British Standard (BS) reference code.