The new Harley Gallery is an award-winning extension to the original Harley Gallery at Welbeck Abbey which houses the Portland collection.
A considerable part of the extension required waterproofing including the main Harley Gallery structure and the adjacent basement ancillary rooms, public conveniences and store rooms – an area of 892m2.
Delta Membrane Systems Ltd was employed as waterproofing consultant to the design team and took care of the project from design stage to completion on site.
Work undertaken and products used
The main gallery slab is recessed below external ground level and it also houses all the environmental controls and plant machinery required to maintain the stringent climatic conditions needed to protect the art works.
The slab was protected by two coats of Delta Koster Deuxan 2C, a polymer modified bitumen mesh reinforced and applied over smooth concrete blinding. This was protected by Delta GeoDrain Quattro drainage and protection membrane, flashed in and buried just below external ground level using a Delta MS Profile Capping Strip.
The adjacent Harley Gallery basement WCs and wash rooms were protected by a combined waterproofing system comprising of two coats of Delta Koster Deuxan 2C, protected by Delta GeoDrain Quattro on the outside, with Delta MS20 cavity drainage DPM over the slab and Delta MS500 cavity drainage membrane over the inner faces of the retaining walls. Underneath this, a pumped drainage system involving mid floor gulleys at regular spacings, linked with a Delta Dual V3 sump and pump system with high water alarm and battery backup was installed.
Internal concrete walls cast upon reinforced concrete kickers were protected from rising damp internally by use of Delta Koster NB1 grey crystalline slurry, applied within the joint and lapped down beneath the Delta MS20 cavity drainage DPM. The DPM was sealed to the faces of the concrete internal walls using Delta Bitumen Primer in conjunction with Delta corner strip wide profile butyl tape to provide an adhesive key.
Caddick Construction and Hugh Broughton Architects were delighted with Delta Membrane Systems' assistance, knowledge and services. Specifications were achieved efficiently and in a timely fashion which exceeded the expectations of all involved.