An Taisce and Cobble Stones at Temple Bar

Mr. Tim O’Sullivan

Director of Traffic

Block 2, Floor 6

Dublin City Council

Civic Offices

Wood Quay

Dublin 8

Dear Mr. O’Sullivan,

I refer to your reply (below) – via Cllr. Andrew Montague – to a query by
An Taisce in regard to why the failed 1990s sett surface on Eustace Street,
Temple Bar, is being relaid again using the same method as that previously
used (copy of original email below). We wish to respond as follows,
including clarification of a number of comments in your email:

* Relaying setts to achieve a tighter smoother surface was not proposed by
An Taisce but by the Temple Bar Framework Plan 2004 (a report commissioned
by Temple Bar Cultural Trust)

* The concerns with regard to the unsuitability of this surface for cycling
are made with reference to Dublin City Council’s current major promotion of
cycling, including the proposed doubling of the Dublin Bikes scheme and
other initiatives such as the government Bike to Work scheme.

* Contrary to the statement in your email, Eustace Street in Temple Bar is
not pedestrianised and is under normal circumstances open to vehicle access
in a south-north direction including bicycles

* Since the sett construction method of a rigid surface with tar-sealed
joints in Temple Bar has broken down and unravelled after only fifteen
years it is self-evidently not capable of sustaining use by heavy delivery
vehicles, thus it is reasonable that questions should be asked in regard to
use of this method again which will need to be relaid again in fifteen
years’ time incurring further time, cost and disruption.

* In nearby Foster Place, an authentic, tar-free or ‘flexible’ historic
sett surface can be seen which has survived virtually maintenance-free for
more than 100 years (see excerpt below from Dublin City
Council-commissioned report Historic Street Surfaces Conservation Study and
Guidance Manual 2009 on the structural integrity of the traditional
flexible sett surface)

* Over the course of the 20th century, hundreds of setted streets in Dublin
were simply tarmaced over, so that a potential vast reserve of historic
stone setts are available for salvage; the notion that these setts are in
short supply or would have to be purchased is thus without real substance

We again call on the City Council to review its sett-laying methods in
Temple Bar. Collectively, we need to get our act together in Dublin in
respect of the cityâ•˙s historic features and surfaces. A huge amount of
damage has been done through lack of engagement of necessary expertise. We
are managing a city which has international renown for literature,
architecture and history and it should be reflected in how we approach and
manage work to the public realm in the historic core. We cannot continue
winging it. City designers in Denmark or Finland would be aghast that roads
and traffic engineers were deciding on and executing works in a
conservation area in a historic district of Dublin without other relevant
input.

Yours sincerely,

Kevin Duff
Dublin City Association Planning sub-Committee

An Taisce
The Tailorsâ•˙ Hall
Back Lane

Dublin 8

Tel. 00353 1 707 70 62

Excerpt from Historic Street Surfaces Conservation Study and Guidance
Manual 2009:

11.2. Structural Capacity
The action of setts is fundamentally different to flagstones in that the
individual stone
units can sustain high vertical loads, and the paved surface derives its
stability from the
joints as well as the bedding.

Traditional setts were split rather than cut, and the rough vertical faces
were laid in ˛dry-boundary manner in contact to each other, the matrix of
stones acting in compression to form a structural unit. The bonding pattern
was important as it locked each sett into position so individual stones did
not come loose and cause the surface to unravel. The joints were filled
with fine sand and setts were laid on flexible sub-bases which have proven
to achieve very high loads. Examples surviving in Dublin around the Guinness
Brewery, notably in Robert Street, have continued to sustain heavy loads
without
deformation or failure and demonstrate the high load-bearing capacity of
historic setts laid in the traditional flexible manner.

In Germany setts continued to be used and maintained throughout the 20th
century, where their use died out in Ireland and Britain. German
experience, as outlined in Vogel, confirms the enduring structural
resilience of traditional setts and asserts that the structural capacity of
a setted surface lies in the design of the support layer. Loads are passed
through the surface layer, and if adequately supported the paving will
withstand even the heaviest traffic as long as it is correctly laid and
bedded.

Now addressed to Councilllor Andrew Montague

The construction method being used in Eustace Street is the same as that
used throughout the rest of Temple Bar. It uses a rigid form of
construction with tar sealed joints. This produces a pavement which is
suitable for use by heavy delivery vehicles and can withstand mechanical
cleaning.

The method proposed by An Taisce involves laying the setts hard against
each other with sand joints. This method in the view of the road
maintenance engineers is not suitable for heavy traffic and will not stand
up to mechanical cleaning which would remove the sand from the joints and
disrupt the structural integrity of the pavement. In addition it would call
for a much increased number of stone setts. In Temple Bar we have used 200
year old ╲bluestone╡ setts. These are in very short supply. It would be
necessary to buy new setts to make up the shortfall which would be created
by using the Construction method proposed by An Taisce.

Relaying the setts even despite the above would be an enormously expensive
proposition. The cost of lifting and relaying setts such as these is around
•400.00 per square meter. This does not include the cost of buying new
setts. I do not expect that money will be available to relay the setts in
Temple Bar generally or even in Eustace Street in the foreseeable future.
Even if the money became available we would strongly advise against
relaying cobbles as suggested.

Finally I would point out that much of Temple Bar ( including Eustace St)
is pedestrianised and cycling is prohibited during operational hours.

Tim

________________________________

From: Kevin Duff
Sent: Tuesday, June 15, 2010 8:34 AM
To: ‘Martin Jordan’
Subject: Current relaying of sett surface, Eustace Street, Temple Bar

Martin Jordan
Senior Engineer, South Inner City
Roads Maintenance Division
Dublin City Council
Civic Offices

Dublin 8

Re: Relaying of sett surface, Eustace Street, Temple Bar

Dear Mr. Jordan,

I write to you in your position as Senior Engineer for the south inner
city, although this issue is addressed to the City Council at a wider level.

We note that the failed 1990s sett surface on Eustace Street, Temple Bar,
is currently being relaid, according to the previous technique with setts
laid widely apart and tar poured between.

1. This is contrary to the Temple Bar Framework Plan 2004, which
recommended relaying setts to achieve a tighter, smoother pattern which
would be more user-friendly for pedestrians, wheelchairs and buggies.

2. If this surface has failed and needs relaying after 15 years, why is the
same tar technique being used again?

Use of tar is not an historical treatment. Note that streets in Dublin
where setts have survived for over 100 years are not tarred and setts are
tightly knitted together – Egs. Foster Place and John’s Lane West, Thomas
Street (see also attached image showing historic-type sett surface at Grand
Place in Brussels).

Notably, the sett surface currently being laid on Eustace Street is
extremely unsatisfactory to cycle on. We should be thinking about this, in
light of the Draft Dublin City Development Plan 2011-17 which contains a
major policy and objective increase with a view to greatly increasing
cycling numbers and provision in Dublin over the next number of years. The
older, tightly-laid sett surfaces referred to form a smooth, coherent
surface which is agreeable to cycle on.

Who is directing works to the public realm in Temple Bar?

Temple Bar is as we know a major tourist product and cultural/historic area
which contributes significant revenue and vitality to the city, so it would
seem to follow that treatment of the public realm should be very carefully
considered and controlled, and that appropriate resources are in place for
its management.

Dublin is in a very unusual situation for a city of its status in that it
does not employ conservation expertise for its historic street furniture
and surfaces. Arising from this, Dublin City Council attracted bad
publicity for butchery of antique stone paving and setts (which were listed
for protection in its development plan) outside the internationally
important Bank of Ireland building on College Green in July of last year.

(We note Policy FC57 of the Draft Dublin City Development Plan 2011-17
providing that work to such elements shall be carried out in accordance
with the Historic Street Surfaces in Dublin Conservation Study and Guidance
Document (2008), and we look forward to implementation of this policy
including repair and making good of previous poor quality work which has
damaged the character of the city.)

With regard to the above, we ask Dublin City Council to review the current
sett-laying practices in Temple Bar.

Yours sincerely,

Kevin Duff
Dublin City Association Planning sub-Committee

An Taisce
The Tailors Hall
Back Lane

Dublin 8