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Recreating the Architecture, Ecology & Experience of Dublin's Townhouses, AD 1014

Third day of thatching
April 16, 2014

Glorious weather is helping the thatching.

Huge crowds are now arriving at the Gardens to admire the work and watch the craftsmanship of Eoin and Peter.

Daniel O'Connel Monument
April 15, 2014

The Daniel O'Connell monument in the next door Glasnevin Cemetery looms over the Viking House. These two building designs date from the same era, even though they seem a world apart.

Second day of thatching
April 15, 2014

The thatch is applied in bundles or 'bottles' of several hundred reeds, which are laid across the roof and temporarily held in position with ash pegs.

The row of bottles is held down by a steel rod or 'ligger', which is attached to the underlying ash battens by wires which can be gradually tightened as the reed is knocked into shape.

Thatching begins
April 14, 2014

Eoin has been joined by Peter Compton of County Cavan. The reed has come from Poland, but is a plant also found in Ireland. The sad fact is that Irish reed is now growing in water that is so rich in nitrates that it is essentially over fertilised. The stems grow too quickly and with insufficient strength, so a roof made from irish reed will have a much shorter lifespan.

Oak and Ash
April 11, 2014

The strength of the Oak and the flexibility of the Ash provide the perfect qualities for their roles; the Oak supports the weight of the roof while the springiness of Ash gives the suppleness to support the reed thatch.

Roof rafters and battens complete
April 10, 2014

The roof is now complete. On Monday morning Eoin will be joined by Peter Compton and the reed thatching will begin.

First of the Battens
April 8, 2014

After splitting the ash poles they are attached to the rafters. The reed thatch will be fixed down on top of these battens.

Cleaving the Battens
April 8, 2014

The scientific name for Ash is Fraxinus excelsior, meaning the 'tall fragile one'. The tree has a natural tendency to split easily.

The individual ash poles are split lengthwise with a cleaving tool to provide the material for the rafters.

The cleaving tool is hammered into the base of the pole which is then carefully levered apart to allow the natural fragility of the wood to split. Preferably a tree should have been felled for a period of about 2 months so that the wood breaks cleanly.

The cleaving brake (right) is the framework which Eoin has built to help him hold the wood while he works on it single handedly.

Roof trimmers
April 7, 2014

The ends of the roof rafters are united by a trimmer, a full ash pole that will help 'kick' the edge of the thatch up at the eaves of the roof.

Roof rafters complete
April 4, 2014

All 44 rafters made from stripped ash poles are now in position. The rafters will now have battens of split ash poles placed at one foot intervals up the roof.

Roof poles in position
April 3, 2014

The two ends of the roof have been finished this evening.

The house has now taken its full form.

Preparing the roof poles
April 2, 2014

The individual ash poles are stripped of their bark in an ingenious clamp set up by Eoin. Two poles set at a very slight angle allow a pole of any size to be held fast by sliding it from one side or the other. The pole can then be cleaned of bark with a spokeshave.

Walls complete
March 31, 2014

End of second week
March 28, 2014

Half Walls
March 27, 2014

The walls are now half-way up.

The butt ends of the rods are slotted into the door frames and the wall height is greatest here, building up a natural curve to the wall height that will match up with the reed thatch in due course.

The Wattle Walls
March 26, 2014

All the wall posts are in and Eoin has started the wattling today, and the form of the house is now taking shape,

The wattle comprises hazel rods harvested last autumn. The weaving starts from the door frames which have a slot into which the ends of the rods are notched.

We will not be applying daub to the building. Whilst archaeological evidence suggests that some walls definitely had daub on the wattle, it is by no means certain that all walls were daubed in mud. It is likely that the houses had many hanging fabrics or animal skins which would have reduced or eliminated draughts through the open wattle walls.

The word wattle is derived from the old English watul meaning a covering.

The Wall Posts
March 25, 2014

The walls are now all but complete, and the hazel wattle will hopefully be inserted by Eoin on Thursday.

The Wall Posts
March 24, 2014

An even wetter (and colder) day.

More than half the wall posts are now in position. Once their bases have been tamped in the hazel wattle will be woven in, starting from the slot in the door posts.

The Corners
March 22, 2014

The walls have started to be added.

Archaeological excavations in Wexford and Waterford reveal more rounded corners to the Viking era buildings of south-east Ireland. Dublin excavations on the other hand reveal houses with more abrupt corners.

International Day Of Forests
March 21, 2014

Today is the United Nations International Day Of Forests.
Forests are central to sustainable development. Globally they cover one third of the land surface of the planet. They harbour exceptionally high levels of biodiversity which, in turn, provide a range of ecosystems services essential for prosperity. Forests provide vital ecosystem goods and services to people, including food, fodder, water, shelter, nutrient cycling and recreation. They also function as carbon storehouses.

Ireland still has one of the smallest percentage areas of forest cover at just over 10%. In the past 20 years the proportion of newly planted broadleaves has substantially increased, however, particularly on privately owned lands, which rose from a 1/4 to half the total forest cover.

Managing woodlands to produce beautiful wood-crafted buildings such as this Viking House was a common feature of the past. But the value of a forest is not just a measure of its timber value, they also provide numerous other benefits that people need to recognise.
The gardens are hosting a conference on Natural Capital: Ireland's Hidden Wealth from April 28-29, 2014. The conference will address the value of all our natural ecosystems, not just the products we derive from them, but for the other services they provide. There is an urgent need to accurately evaluate these benefits and costs of our relationship with the environment in economic terms, as the impacts of diminishing resources, increasing environmental degradation, and climate change, become more and more apparent.

The Trestles
March 20, 2014

A wet day today, but the two trestles give an idea of the final house shape.

The frames already give a sense of enclosure of the future house.

The Trestles
March 19, 2014

The two trestle frames were raised today. These massive structures are made from green (unseasoned) Oak and each weigh about half a ton.

In the original houses these posts were probably much smaller and left in the round.

The Thatch
March 18, 2014

The 1,400 bundles of reeds have arrived and are now on site. The reeds probably weigh in excess of 3 tons. The roof will be finished off with a ridge of oaten straw.

The thatch will form an important habitat for solitary bees which will use the hollow reeds as a nesting site.

The Joints
March 18, 2014

The main strength of the building lies in the two oak trestles at each end. These comprise the 6 inch square door posts at each end which are linked with cross-pieces to two 8 inch square posts that lie inside the building.

The door lintel extends well beyond the door frame (right) and is supported by two further oak uprights that the last weave of the wattle wall will enclose. The door posts have a slot on their outer face to accept the hazel wattle rods to give the wall a neat finish.

The trestles should be up by tomorrow evening!

Easter Week
March 17, 2014

The Viking House should be completed by Easter. To mark the occasion during Easter week (14th to 28th April 2014) we hope to have the replica Viking Ship ‘Gro’ on display in the National Botanic Gardens.

Constructed from Irish oak by Danish boatwrights using techniques employed in Dublin 1,000 years ago, the boat will be on loan from the Ferrycarrig Heritage Park.

Materials: Ash
March 17, 2014

The roof will be constructed from 52 peeled ash poles. These have been selected for their straightness, even though some have remarkable spirals caused by strangulation by honeysuckle plants.

Materials: Oak
March 17, 2014

The walls will comprise 38 rounded oak uprights onto which the hazel wattle will be woven.

The Tools
March 17, 2014

The Viking settlers in Dublin were sophisticated craftsmen and builders.

It is now known that large, seagoing warships were being built in Dublin from Irish oak.

In 1962 such a ship was discovered in Denmark at Skuldelev. This had been built near Dublin in 1042. A reconstruction – the Sea Stallion of Glendalough – was sailed back to Dublin from Roskilde in 2007.

The Craftsman
March 17, 2014

Eoin Donnelly is now on site and will begin erecting the two oak trestles this week.

There are six oak uprights at each end of the building. These will be decorated with carved motifs once the building is completed.

Eoin uses a range of tools, including adzes and spokeshaves - technology that has remained virtually unaltered for a thousand years or more.

Preparing the trestles
February 15, 2014

Eoin was filmed in his workshop in Co Wexford by Philip Bromwell on Vimeo.

This RTÉ news report was shot on an iPhone 5S, as part of a wider mobile journalism project in RTÉ, Ireland's national broadcaster.

Harvesting the Materials
February 15, 2014

The house will be built from oak, ash and hazel.

The Oak tree from which the main uprights are made was a 250 year old tree grwoing in County Wicklow.

The hazel rods and ash poles have been sourced from Ballykillcan Woods. A well managed ash woodland will produce the 100 required poles from less than an acre of land, and the cut stems will resprout to replace these poles in about 8-10 years.

The hazel rods have been harvested from a similar area and will regrow in 5-7 years.

The Design
February 15, 2014

Dublin Houses from the 8th to 10th Century were modelled on a similar and distinctive Hiberno-Norse style.

The roof was supported by upright posts (b), and the walls were built of hazel wattle with rounded corners. Two large beds (g) faced one another across the central hearth (f). In each corner of the building were areas for storage (d).

The botanical evidence gathered from the excavations was extensive and will guide our work in constructing a Viking Garden around the finished house.

The first Hiberno-Norse house in Dublin for 1000 years
January 14, 2014

The building will be authentic in both detail and material. It will be the first time such a replica building has been constructed in Dublin for 1000 years.

The finished building will serve as a classroom for our education programme, introducing people to the ideas of Dublin's early history, how archaeological evidence is gathered and understood, and sustainability of construction when a building is 100% organic.

Wood Quay and Fishamble Street
January 14, 2014

In 1961 remarkable discoveries were made in the region of Wood Quay and Fishamble Street, Dublin. These turned out to be the perfectly preserved remains of Viking Dublin, dating from the 8th to the 10th Century.

Between 1974 and 1981 dozens of buildings and streetscapes were excavated by the National Museum under the direction of Pat Wallace.

Unfortunately, even the best efforts of Mary Robinson (later the 7th President of Ireland) failed to save these discoveries from development.

The house has come about through the enthusiastic support of many partners especially Dublin City Council, the National Museum of Ireland and the School of Archaeology, University College Dublin. We have received generous financial assistance from the Irish Museums Trust and Dublin City Council.