Construction Tech & Environmental Services Level 2 Flashcards
On Project Weymouth, when considering the various options for lifts, did you consider any impact on the building services, such as electrical requirements?
As part of my options appraisal, I did indeed consider the impact on building services. For example electrical requirements. When considering the various options, this was done alongside the mechanical and electrical consultants, who were fortunately able to advise that the existing power was sufficient for accommodating even the option with the highest power loading requirements.
On Project Weymouth, was there any impact on the building’s foundations or structural frame to consider when comparing the options for the lift?
Yes, Option 1 involved a deeper pit depth. So, the structural engineer was required to advise as to whether the foundations required additional support - of which they did not.
Then, the lift shaft acts as a vertical load bath within the buildings frame. So, for the larger capacity lift, a new shaft was required not only for size but to support structurally.
Option 2 required alterations to the existing shaft, so additional structural supports to support the load.
Ultimately, Option 4, the hydraulic lift was the chosen solution. As the existing shaft and pit could be utilised, along with the existing motor room.
On the Oxford St Project, did you consider any other design options other than the client’s preference for insulation and floating screed?
Yes, so initially the option was considered for pouring a bonded screed to build up the floor levels. However, because of the significant depths required to be built up, this posed the question in relation to several aspects of the building:
- the loading of a screed of this thickness, and the impact this would have on the structural stability of the slab
- the impact on programme with reference to the drying time in laying a screed of that thickeness
- the location of the store being in Oxford street, there may have been certain limitations surrounding being able to pump the screed, and then the cost and time implications of hand laying
On the Oxford St Project, did you consider the programme implications and the costs associated with a longer programme duration for building up the flooring?
Yes, through liaising with specialists, I could ascertain the anticipated drying time and expected duration.
I was also able to ascertain the difference between timescales in utilising a screed pumping truck and laying by hand in the event permits for the trucks could not be obtained.
Did you consider lifecycle costing within the lift options?
Yes, this was considered.
For example, for the platform lift, despite this being the least capital outlay, in terms of lifecycle costing, this was not most economically efficient. Platform lifts typically move slower. And due to the size of the store and the proposed use of the lift, the lift engineers had raised concerns in relation to more breakdowns.
In addition, the chosen option, the hydraulic lift, the lift engineer had informed me that hydraulic lifts often require more maintenance call outs than mechanical lifts. However, given this option did note require a new shaft or pit and the existing motor room could be utilised, along with meeting the end users needs, this was considered the best option.
On the Oxford Street retail project, what would a section through the floor have looked like for a floating screen versus a bonded screed.
So, from the bottom up -
The floating screed would be:
- concrete slab
- DPM
- insulation
- slip membrane to separate insulation from
- then the screed
- steel mesh as unbonded screeds have a tendency to curl and crack
- floor finish
The bonded screed would be:
- concrete slab
- bonding agent
- screed
- floor finish
