Wren Hall Specification of Works Specification 10-MC
Phase 2
December 2017
Specification 10-MC is for main building work in Phase 2 of the alteration to Wren Hall at Wroxall, Warwickshire.
Brief construction history of Wren Hall
The building was originally a school hall with the master’s house attached at the east end. The polychromatic brick section was built in the 1840s in Victorian Gothick style.
The Victorian building had a blue brick Arts & Craft style west wing added in the first decade of the 20th Century. This work also removed the original heating stoves and replaced them with a solid fuel heater in a sunken boiler room providing heat to cast iron radiators in the Halls and West Wing,
A range of outbuilding also existed in the space north of the original hall that was likely to have been the original toilets and outbuildings. These were removed in the late 1960s when the village school was modernized by WCC to include the construction of indoor toilets in the west wing, a new kitchen and offices under a felted flat roof. The original floors in the oldHall was replaced with a suspended concrete slab construction and the Hall windows were replaced with metal framed units. .A large opening with sliding folding doors was formed in the main Hall north wall to provide access to the Kitchenservery.
When the school became redundant the building was sold to the local Community which has run the building since then. This 1960s construction is still in existence and in 2016 obtained planning permission and listed building consent to be altered in accordance with the scheme shown in drawings:Wroxall 17-02. The .Phase 1alterations (Rooms 4,5,6,7 & corridor)involve internal changes to the west wing and Phase 2 is the demolition of the 1968 flat roof area (shown on drawing 17-10) for the construction of a new large hall and new entrance block.
Phase 1 of this scheme involves removing the existing toilets in the west wing and constructing new facilities which includes a new kitchen enclosure. A new west entrance door will be constructed as part of this phase. The Phase 1work is described in specifications 1 to 7 and will be complete before Phase 2 is started. See drawing Wroxall 17-31 to identify the phases..
The original School Master’s House passed into different ownership in 2017 and is now a separate dwelling but has a flying freehold over a section of the east corridor.
See Specification 10-E for details of the electrical Work
See Specification 10-H for details of the Heating & Ventilation Work
Table of Contents
C Existing site/buildings/services
Demolition
Damp proof course renewal/ insertion
Cavity wall tie renewal/ insertion
Fungus/ beetle eradication
DGroundwork
Excavating and filling
EIn situ concrete
In situ concrete
Formwork for in situ concrete
Reinforcement for in situ concrete
FMasonry
Brick/ block walling
Natural stone
Accessories/ sundry items for brick/ block/ stone
GStructural/Carcassing metal/timber
Structural steel framing
Isolated structural metal members
Carpentry/ timber framing/ first fixing
HCladding/Covering
Plain roof tiling
Lead sheet coverings/ flashings
Stainless steel strip/ sheet coverings/ flashings
JWaterproofing
KLinings/Sheathing/Dry partitioning
Plasterboard dry linings/ partitions/ ceilings
Wood strip/ board fine flooring/ linings
LWindows/Doors/Stairs
Windows/ rooflights/ screens/ louvres
Doors/ shutters/ hatches
Stairs/ ladders/ walkways/ handrails/ balustrades
General glazing
MSurface finishes
Cement based levelling/wearing screeds
Resin flooring
Plastered/ rendered/ roughcast coatings
Stone/ concrete/ quarry/ ceramic tiling
Wood block/ composition block/ mosaic parquet flooring
Decorative papers/fabrics
Painting/clear finishing
NFurniture/Equipment
General fixtures/ furnishings/ equipment
Sanitary appliances/ fittings
PBuilding fabric sundries
Sundry insulation/ proofing work/ fire stops
Foamed/ fibre/ bead cavity wall insulation
Unframed isolated trims/skirtings/sundry items
Door/ window ironmongery
Trenches/ pipeways/ pits for buried engineering services
Holes/ chases/ covers/ supports for services
QPaving/Planting/Fencing/Site furniture
Site/street furniture/equipment
RDisposal systems
Rainwater pipework/ gutters
Foul drainage above ground
Drainage below ground
SPiped supply systems
See separate Heating & Ventilation Specification 10-H
TMechanical heating systems
See separate Heating & Ventilation Specification 10-H
VElectrical supply/power/lighting systems
See separate Electrical Specification 10-E
UVentilation/Air systems
See separate Heating & Ventilation Specification 10-H
ZBuilding fabric reference specification
Purpose made joinery
Purpose made metalwork
Preservative/ fire retardant treatment
Fixings/ adhesives
Mortars
Sealants
DRAWINGS
17-02General Arrangement (Phase 1 & 2)
17-04Side door and windows (Phase 1)
17-05Entrance Ramp (Phase 2)
17-06 Block Paving (Phase 1 & 2)
17-09 Site Location Plan
17-10Survey plan & existing heating pipes
17-16New Toilets (Phase 1)
17-17Electrical Drawing (Phase 1 & 2)
17-21Diagrammatic drawing of the existing plumbing installation
17-26Wall Finishes (Phase 2)
17-31Survey Plan with Phases 1 & 2
17-32Kitchen layout (Phase 1)
17-33Window details (Phase 2)
17-34 Heating layout (Phase 2)
17-37Ventilation Ducts (Phase 2)
17-38Roof finishes (Phase 2)
17-39Roof Structure (Phase 2)
17-40Door details (Phase 2)
17-42Floor Finishes (Phase 2)
allHa
These drawings are available on the Wren hall website:
A. Existing site/buildings/services
A/1.The building has the following mains services:
Electricity,
Water, -Severn Trent.
Gas,
Waste disposal, - Warwick District Council
Sewage, an onsite sewage treatment facility
A/2. See drawing Wroxall 17-10 & 17-34 for indication of known services. Note; these have been taken from old drawings and have not been surveyed.
A/3. Older service pipes are likely to exist due to the age of the building and the number of alterations over the last 150 years.
A/4.The Contractor is required to co-ordinate the provision of a new control panel to the electrical supply in the lobby at the west end of the building. Install ducts for the existing main incoming cable where it will be under the new Entrance Block floor. Details of the new electrical system for the building are shown in section V.
A/5. The Contractor is required to include and co-ordinate the extension of the existing water main for provision of a water supply to the east end of the building in a duct and to provide a cabinet for the water meter where indicated on drawings..
A/6. The Contractor is required to co-ordinate the provision of an extended gas supply pipe to the new Meter in a new wall cabinet and provide a gas supply to the boiler in the Kitchen;Room 4.
A/7 The Electrical work is being arranged as a sub-contract that will be a nominated sub-contractor to the Main Contractor. The tenders for the main building work are invited to submit a price for the Electrical Installation with their building tender if they wish.
B Heating
B/1.The current heating is supplied by a gas fired boiler in the eastern Boiler Room. This is a low pressure hot water system heating radiators calorifiers and hot water cylinders for washing.The pipework uses a pressurise system.The pipe distribution is a complicated layout reflecting the hundred year old installation and the changes. The primary flow is through a pump assisted three inch diameter cast iron pipes rising to high level in the Halls,(Rooms 1 &2),this heats cast iron radiators in the West Wing (Rooms 4, 5 & 6 & 7) and the Halls using a single pipe flow and return. A plumbing schematic of the system is shown on drawing 17-21.
B/2. The single pipe supply drops to ground level in the north east corner of the West Wing and runs at low level around the external walls serving the radiators under the windows.
B/3. The 1962 extension introduced a copper pipe sub-system to heat the Kitchen and new rooms. Sections of the copper pipe circuit are buried in the floor slab and the exactline of the runs is not known. This buried copper pipe system will be abandoned by the work in phase 2 .
B/4. A new heating system is required for the altered building using a new gas heater in the replacement kitchen (Room 4) with a new gas supply and aconcentric input air / exhaust gases flue to the roof.
The new Boiler will be connected to the west wing old halls and new rooms servingnew steel panel radiators which will replace the existing cast iron radiators. All radiators are to be fitted with thermostatic valves.
B/5. Hot water for the kitchen and toilet washbasins will be supplied by a new mains pressure hot water cylinder mounted at high level in the kitchen.
B/6The new heating system is being arranged as a sub-contract that will be a nominated sub-contractor to the Main Contractor. The tenders for the main building work are invited to submit a price for the Heating Installation with their building tender if they wish.
C Demolition
C/1SURVEY
•Scope: Before starting work, carry out a survey and submit a report and method
statement covering the following:
- Condition and demolition methods and sequences for the structures.
- Removal methods of any hazardous materials.
- Protection to adjoining house which will be adversely affected by the Works.
- Identification, location, disconnection and removal of services.
- Arrangements for protection of personnel and the public.
- Arrangements for control of site materials and compound.
- See drawing Wroxall 17-10 for a drawing of the building as existing in 2017.
C/2EXTENT OF DEMOLITION
•General: Subject to retention requirements specified elsewhere, demolish structures down to Slab Level for internal partition walls and down to foundations for north east external wall. See drawing Wroxall 17-31 Phase 2 Demolitions..Generally the 1960s building will be removed and the remaining structures is to be preserved. Note this building is Listed Grade 2.
C/3FEATURES TO BE RETAINED
•General: keep in place and protect the following: all walls identified to be retained as part of final scheme. Specific care to be taken for: the Party Wall to the adjoining house; room above east corridor belonging to adjoining house; all elements of the 1840s and 1900s Listed building, excluding the services.
C/4LOCATION OF SERVICES
•Services affected by the Works: Locate and mark positions.
•Mains services: Arrange with the appropriate authorities for locating and marking
positions. Arrange for the services providers to move or alter incoming services as shown on drawings.
Protect services to adjoining house inside area of new works
C/5DISCONNECTION OF SERVICES ARRANGED BY CONTRACTOR
•Responsibility: Before starting demolition arrange with the appropriate authorities for
disconnection of services and removal of fittings and equipment.
Water Services. Existing incoming main supply pipe
Gas supply to boiler and appliances: Meter to be moved to west of building.
Electrical supply to Wren Hall. Minimise the time that Wren Hall is without power.
C/6DISCONNECTION OF SERVICES ARRANGED BY EMPLOYER
•Responsibility: The Employer will arrange disconnection of services and removal of fittings and equipment prior to demolition: Security Alarm system.
•Before starting demolition ensure that disconnections have been carried out.
C/7DISCONNECTION OF DRAINS
•General: Locate and disconnect all disused drain connections. Permanently seal within
the site.Drains from the Disabled WC, Utility Room, Kitchen, Boiler Room, Kitchen Yard.
C/8DRAINS IN USE
•General: Protect drains and fittings still in use and keep free of debris at all times.
•Damage: Make good any damage arising from demolition work. Leave clean and in
working order at completion. Drawing 17-34 shows the known drains on site but others are likely to exist. Note the House drain connects into the Wren Hall system.
C/9BYPASS CONNECTIONS
•General: Provide as necessary to maintain continuity of services to occupied areas of the
same and adjoining properties: Adjoining House. New Toilets and New Kitchen in Phase 1.
•Notice: Give adequate notice to occupiers if shutdown is necessary.
C/10SERVICES WHICH ARE TO REMAIN
•Damage: Give notice and notify the service authority or owner of any damage arising from the execution of the Works. Protect services to adjoining house.
•Repairs: To the satisfaction of the CA and service authority or owner.
C/11WORKMANSHIP
•Standard: Demolish structures in accordance with best practice.
•Operatives: Appropriately skilled and experienced for the type of work and holding or be
training to obtain relevant Certificates of Competence.
•Site staff responsible for supervision and control of work: Experienced in the assessment
of risks involved and methods of demolition to be used. Keep adjoining owner informed of the times of noisy or dusty operations.
C/12SITE HAZARDS
•Fire or explosion caused by gas or vapour: Prevent.
•Dust: Reduce by periodically spraying with water.
•Site operatives and general public: Protect from vibration, dangerous fumes and dust
arising during the course of the Works.
C/`13ADJOINING DOMESTIC PROPERTY
•Temporary support and protection: Provide at each stage.
•Damage: Prevent. Promptly repair. Leave no unnecessary or unstable projections.
•Support to foundations: Do not disturb.
•Defects: Report any defects exposed or becoming apparent.
Minimise inconvenience to adjoining property.
C/14STRUCTURES TO BE RETAINED
•Parts which are to be kept in place: Protect. In particular, safeguard wall to existing Halls and West Wing of building.
•Extent of work: Cut away and strip out the minimum necessary.
•Debris: Prevent from overloading any part of the structure which is not to be demolished.
C/15PARTLY DEMOLISHED STRUCTURES
•General: Leave partly in a stable condition, with adequate temporary support at each
stage to prevent risk of uncontrolled collapse.
•Debris: Prevent from overloading scaffolding platforms.
•Unauthorised persons: Prevent access. Keep safe outside working hours.
Note the north wall of the Hall (room 1) was altered in the 1960s by insertion of a large opening into the Kitchen which may have weakened the structure.
C/16DANGEROUS OPENINGS
•General: Illuminate and protect as necessary.
C/17ASBESTOS BASED MATERIALS
None have been identified but ondiscovery: Give note immediately of any suspected asbestos based materials discovered.
Avoid disturbing such materials and submit details of methods for safe removal.
C/18UNFORESEEN HAZARDS
•Unrecorded voids, tanks, chemicals, etc discovered during demolition: Give notice.
•Method for safe removal: Agree with Client’s representative.
C/19SITE CONDITION AT COMPLETION
•Debris: Clear away and leave the site tidy on completion.
C/20CONTRACTOR'S PROPERTY
•Components and materials arising from the demolition work: Property of the Contractor
except where otherwise provided. Remove from site as work proceeds.
C/21EMPLOYER'S PROPERTY
•Components and materials to remain the property of the Employer: Description: All materials outside the defined demolition area. The Disabled toilet and fittings carefully remove for reuse/Stone Notice block built into wall
•Protection: Until removed by the Employer, reused in the Works or end of the Contract.
C/22RECYCLED MATERIALS
•Materials arising from demolition work: May be recycled or reused elsewhere in the
project, subject to compliance with the appropriate specification. Save existing external bricks where able to be used for making good and repairs
C Damp proof course renewal/ insertion
C/23SURVEY OF EXISTING WALLS
•Survey generally:
- Purpose: To identify the presence and extent of any rising damp
- Remedial work: Nature and extent of work required to ensure an effective dpc.
- Other information: Any considered relevant.
Note the walls to the old Hall (room 1) are solid masonry construction.
C/24BEFORE DPC INSTALLATION
•Internal finishes: Remove only sufficient to expose the proposed line of any new dpc.
•Fungal or beetle attack to timber sections: Report any occurrences.
C Fungus/ beetle eradication
C/25SURVEY AND REPORT
•Survey generally: Survey all portions of the roofs affected by new works.
- Purpose: To ascertain nature and extent of any fungal and/or beetle attack. To ascertain sources and extent of any dampness.
Report to Clients representative the findings
•Survey report content:
- Factors affecting execution of the work: Identify any site conditions and restrictions
including the presence of bats.
- Eradication treatments and procedures: Submit proposals and quantities.
- Associated work: Nature and extent of repair and/ or replacement work required to
building fabric.
- Other information: Any considered relevant.
C/26FUNGAL ATTACK
•Extent of cutting out/ removal of building fabric: Submit proposals.
•Dry rot:
- Fruiting bodies: Spray with fungicide. Remove carefully and clean down surfaces.
- Infected materials: Remove immediately and dispose of safely.
•Wet rot: Cut out rotten timber.
C/27BEETLE INFESTATION
•Extent of cutting out/ removal of building fabric: Submit proposals.
•Infected timber: Cut, scrape and trim back to sound timber. Remove debris immediately
and dispose of safely.
C/28TIMBER PRESERVATIVES/ MASONRY FUNGICIDES GENERALLY
•Products: Registered by the Health and Safety Executive (HSE) and listed in HSE
publication 'Pesticides'.
•Application: In accordance with statutory conditions of approval given on product labels.
C/29GUARANTEE
•Type: Insurance backed. Administered by an independent insurance protection company.
- Guarantee period (minimum): 20 years from Practical Completion.
•Documentation: Provide certificates/ guarantees at Practical Completion.
D Groundwork
D/1 Excavating and filling
Work relates to new foundations for the new Hall and filling the old Kitchen Yard. See drawing 17-10 runs
D/2OBSTRUCTIONS
•Recorded foundations, beds, drains, etc: Break out and seal off drain ends. Remove
contaminated earth.
•Unrecorded foundations, beds, basements, filling, tanks, service pipes, drains, etc: Give
notice.
D/3EXCESS EXCAVATIONS
•Excavation taken wider or deeper than required: Backfill with weak mix 1:15 concrete .
D/4SURPLUS EXCAVATED MATERIAL
•Material not specified to be spread and levelled: Remove from site, including all
sub-grade clay material.
D/5HAZARDOUS, AGGRESSIVE OR UNSTABLE MATERIALS
• Generally: Do not import or use fill materials which would, either in themselves or in