The Vinery - National Trust

Greenway, Devon
Building design guide
n engagement
n period restoration
n environmentally friendly paint
n use of Direct Labour teams
The Vinery
Repair and conservation of early nineteenth-century vinery
2006
Building design guide
Project brief
■ Repair and conserve the Vinery, restoring it to its original
Georgian-style fenestration, framework and structure.
■ Return it to traditional use as part of the visitor display
within the garden, replanting it appropriately.
■ Make the project an exemplar of regional staff skills and
expertise in traditional repair techniques to demonstrate the
quality and cost efficiency of using the Trust’s in-house Direct
Labour team.
Key factors
■ Archaeological investigations carried out to inform
restoration
■ Original narrow glass structure matched
■ In-house Direct Labour teams using traditional
conservation techniques
■ Importance of visitor engagement
Designations
■ Registered Park and Garden of
Historic Interest Grade II
■ Greenway House: Listed Grade II*
■ South Hams AONB
Consultees
■ Donor family
■ South Hams District Conservation
Officer
The interior of
the Vinery during
restoration
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Building design guide
Reconstruction
of the roof
Design approach
■ The Vinery was built between 1839 and 1865. It is a
timber-framed, three-quarter span glasshouse. It has eleven
bays with polygonal return bays at each end of the building
on a red brick apron wall.
■ It stands in the walled kitchen garden of Greenway,
a Grade II* listed building, which was built 1780-90,
remodelled and extended in the early nineteenth-century,
and acquired by the National Trust in 2000.
■ The Vinery was originally built to accommodate early
narrow cylinder glass and was converted to take improved
or broad cylinder glass when it became available (post-1845
when the glass tax was abolished).
■ There were no good surviving remnants of the fenestration
from this altered form, however, there is excellent evidence
of the original form which took the narrower glass. Because
of this, the intention was to conserve and repair the Vinery to
match the original narrow glass structure.
Modern alternatives
North American Douglas fir was used
for all work due to its low knot nature
compared with European timber. All
timber was obtained from sources
certified by the Forest Stewardship
Council and evidence of compliance
provided. Linseed oil paint was used
instead of the original lead-based paint.
Conservation and
archaeology
The glasshouse was in a fragile condition
and had undergone several phases of
repair although key areas of original
fabric remained. In order to inform
repair proposals and the Listed Building
Consent application, a measured survey
of the structure was undertaken by Exeter
Archaeology in 2004. This included
selective excavation and investigation.
The work recorded the evidence for
the use of original narrow cylinder glass
and uncovered the original stoves and
flue system. The decision was made
to repair or renew largely to the original
design, as later repairs were generally
of poor quality and in poor condition.
Surviving original remnants were used for
reconstruction work.
Engagement
Works were fenced off in a way that
enabled visitors to stand back and
view progress. A joinery stand was set
up to demonstrate the use of the
traditional skills.
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Building design guide
Project team
Site issues
■ Greenway is subject to a Section 106 Traffic Management
Policy imposed by the Local Authority. This meant that all vehicle
movements had to be minimised and a weight restriction of 10
tonnes was applied to regular deliveries.
■ The Greenway site was kept open throughout the work. As
the Vinery is the first view of the garden for the visitor, care was
taken to ensure that visitors still felt welcome while works were
underway.
New roof sashes were fabricated by the Direct Labour team
The project team comprised people and companies
providing internal and external expertise including:
■ Architect
■ Consultant Engineer
■ Project Manager
■ Building Surveyor
■ Curator
■ Gardens Advisor
■ Archaeologist
■ Conservator
■ Planning Supervisor
■ Direct Labour Co-ordinator
■ Clerk of Works
■ National Trust Direct Labour team
■ Painter: Kevin Sussex
■ Glaziers: Roman Glass
■ Scaffolding: Hammer Scaffold
■ Metal Work: Branscombe Forge
Detail of the roof ridge before restoration
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Building design guide
Products and services
■ Glass supplier
Tatra Glass
Duke Street
Loughborough
Leicestershire, LE11 1 ED
www.tatra-glass.co.uk
The central partition wall was recreated in the Killerton workshop
Construction
Structure
The original timber framework was constructed in softwood,
probably imported from the Baltic, but timber of suitable quality
is now unobtainable from this source. Replacement framework
used Douglas fir specified to BS 942:1996 to meet the
requirements of a severely hostile environment while maintaining
the Trust’s commitment to sustainability and avoiding the use of
toxic wood preservatives.
Pitch pine was considered but rejected since it is untreatable,
is weaker, has a short life-time and is too susceptible to
woodworm. There were also doubts about finding certifiably
sustainable sources.
Brickwork
The brick apron wall was in sound condition and required no
repair work of significance. The original vine slots were opened
up so that vines could be grown to inform and educate visitors
about the original purpose and function of the house. No attempt
was made to reproduce the staging that apparently was once
The vine slots were reopened to enable vines to be grown again
fixed to the north wall. Along the inside face of the external wall
is a horizontal tile-capped brick flue, the only one which survives.
Although no longer functional, it was repaired as a record of the
original heating system.
Interior after planting; tiled heating flues
along outer wall
Partition
The structure was enhanced by the re-introduction of the central
partition that was fixed directly to the central rafter assembly,
thereby imparting additional support to the neighbouring
assemblies on each side. This replicated the original partition, its
design being based upon the surviving evidence and traditional
precedent. A detailed drawing was provided, and the new wall
constructed to match the existing brickwork in colour, texture,
mortar and bond. The compartmental design allows the heating
level of each compartment to be adjusted to suit different
planting requirements.
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Building design guide
external woodwork. The colour matched the original colour as
closely as possible. Samples of the original colour were retained
intact to validate this course of action for future generations.
Structural support
Windows installed and in the lower wall, the flue is revealed
Fenestration
The modern galvanised steel posts supporting the ridge
internally were removed because they interfered with the visual
appreciation of the historic form. New stainless steel brackets
were inserted at the rafter mullion eaves junction to support the
load and make up for the inherent frailty of the structure. These
did not seek to impersonate traditional brackets of this type often
used in traditional glasshouse construction, but were a plain
expression of their function.
Some of the original high level iron ties that contributed to
the stability of the structure had disappeared and these were
replaced to match the survivors.
■ Ironmongery
Select Architectural Ironmongery Ltd.
85a Kingsway Avenue, Paignton
Devon TQ4 7AB
■ Purpose-made Ironmongery
Branscombe Forge, Branscombe,
Seaton, Devon EX12 3DB
www.branscombe-forge.com
■ Paint supplier
Holkham Linseed Paints
The Clock Tower
Longlands, Holkham
Wells-Next-The-Sea
Norfolk NR23 1RU
www.holkham.co.uk/linseedpaints
No original glass survived, so all new glazing was fixed in the
traditional manner. It was overlapped on bed putties only, using
genuine mouth-blown narrow cylinder glass imported from
Poland. Samples were provided for approval before commencing
work.
Painting
An analysis of the surviving, original nineteenth-century paint
coatings showed an early scheme of beige-yellow lead paint,
based on an iron oxide pigment, which was likely to have
been obtained locally. Whilst the Trust would normally desire to
reproduce original colour schemes exactly, both in colour and
material, health and safety requirements and environmental
considerations dictated that redecoration with genuine lead
paint was not a viable option for a building open to unsupervised
public access. Repainting was done using a traditional
linseed oil paint imported from Sweden and in common use
in Scandinavian countries for the protection and decoration of
The Vinery in May 2005
The new partition wall in situ
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Building design guide
Rainwater disposal
There was no evidence of previous rainwater collection from the
roof. A solid timber gutter system based on traditional precedent
was considered but rejected. Instead, an anti-splash margin
was installed at the foot of the wall to avoid erosion of the lower
courses of brickwork.
■ Metalwork conservation
(stoves)
Rupert Harris Conservation
Studio 5c, Block A
1 Fawe Street, London E14 6PD
www.rupertharris.com
Direct Labour team
The old stoves, shown prior to conservation,
which used to heat the vinery
Work was carried out carefully by the in-house Direct Labour
team, based at Killerton, Bodmin and Saltram Yards, using
traditional joinery repair techniques. Casement and sash
windows were produced at Killerton in order to make the most
of the regional expertise.
The Direct Labour team at work
Stoves
The original cast-iron stoves survived intact but were severely
decayed at low level within the potting shed on the north side of
the house. Because they are rare nineteenth-century examples
of their type, archaeological investigations were carried out.
Alterations were made to surrounding masonry in order to create
ideal viewing conditions. The stoves were conserved and put on
display to visitors to show how these glasshouses were heated
and to convey the tasks associated with horticultural activities
of the period. No form of modern heating was introduced into
the glasshouse.
Paths and beds
The stone path within the Vinery was retained intact and the
planting beds were cultivated to grow specimens representative
of the horticultural history of the house. The path leading to the
potting shed was retained and made good with matching tiles
salvaged from elsewhere within the walled garden; it is likely that
these tiles had been taken from the Vinery.
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Building design guide
Procurement
There was no tendering process as the project was undertaken
using the in-house regional team.
The Architect was selected for his expertise regarding
glasshouses, as recognised by the National Trust and English
Heritage.
Costs
The total project cost was £148,349 with a cost per m2 of
£1,571.50.
Funding
The dereliction of the building and urgent need for repair drove a
local, extremely successful funding appeal.
The project was largely funded by the National Trust. However,
27% of costs were met from grants, trusts and other fundraising.
Restored roof showing details of
the sash pulley
New steel rafters and mullion
brackets support the roof
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Building design guide
Post project review
Best practices
■ The importance of the use of conservation statements in
the conservation planning of the project was acknowledged
by English Heritage who included the Greenway Vinery project
in their guidance document circulated to all English planning
authorities.
■ Use of the Trust’s Direct Labour team made for a flexible and
more cost-controlled project. The staff’s knowledge of the Trust’s
working practices and standards made it easier to deal with any
problems that arose.
■ Although the specialist architect’s involvement incurred extra
cost, his experience and ability was considered to outweigh the
expense.
Lessons learnt
■ Preliminary estimates of the amount of original joinery that
could be saved proved optimistic. Fortunately, the difference
was not too great but it could have created the necessity for a
submittal of a fresh Listed Building Consent application. To add
interest for visitors and as a record, representative samples of
each type of component were retained and repaired by
piecing-in.
■ Drying times of the linseed oil paint were longer than expected.
The sashes still stick when the paint warms up. It pays to coat
the sash runners with candle wax before fixing.
■ Travelling times to the site were an issue for the Direct Labour
team, especially in the summer. However, this was offset as far
as possible by conducting works off site.
The roof during reconstruction showing
the restored structure and flashing
■ Unfortunately the choice of a traditional linseed oil paint
has proved problematic. It attracted a black fungus which
dramatically altered the appearance of the whole structure.
Linseed oil has a slow drying process and always remains
slightly tacky. Pollen, dust and other matter may have settled
in the paint and contributed to fungal growth. There was also
some crazing and it is suspected that the linseed oil paint
reacted to the dipping and stripping process used to remove
old paint from the frame. When redecoration is carried out
strong consideration will be given to using a modern paint
system such as Dulux Weathershield, Sikkens or Rustoelum
all of which have already been used at Greenway.
Feedback
■ Very popular feature with visitors (31,600 visitors in 2007).
Comments from visitors are extremely positive, especially
now that the beds have been planted and the building is once
again functioning as a glasshouse.
■ The donor family were exceptionally pleased with the result.
Over time the linseed oil paint
has become stained by a black fungus
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Building design guide
Further information
If you require this information in alternative
formats, please telephone
01793 817791
or email
buildingdesignguide@nationaltrust.org.uk
Contact the property at:
Greenway Road, Galmpton, nr Brixham, Devon TQ5 0ES
www.nationaltrust.org.uk/greenway
Acknowledgements
Content: Rick Meier, Robyn Brown, Paul Baker, Bill Baker, Ingrid
Chesher, Angela Collins and Jacky Ferneyhough.
Design: Inkcap Design
The Building Design Guide concept was devised by Rory Cullen and developed
by Jonathan Howard, with acknowledgements to Jacky Ferneyhough,
Ingrid Chesher and Angela Collins.
Copyright: The National Trust retains copyright for this document. Please do not
reproduce/photocopy without prior permission.
Products and services: Use of products and services is not necessarily an
endorsement by the National Trust.
The completed
structure
Left: Greenway
Right: Sideview
© The National Trust 2013. Registered charity no. 205846.
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