Introduction
A total of 541.03kg of Ceramic Building Material (CBM) was examined from the excavations; this total
included 7.91kg of stone building material such as roof and floor tiles. The CBM is discussed in
detail for the whole site and on a phase by phase basis elsewhere within the report. Much of the
material from Walmgate was fragmentary, but some complete and almost complete examples of various
forms were recovered. A broad range of forms was identified; most were medieval in date, but some
Roman, post-medieval and modern forms were also present.
Methodology
The CBM was examined by a x10 hand lens and matched with the York fabric series. The fabric series
is divided into Roman (R), medieval (M), floor tile (F), pan tile (P), post-medieval/modern (P0)
and stone (S). The material was then recorded on a YAT pro-forma which noted the fabric number,
form name, corners present, weight, length, breadth, thickness, presence of mortar, comments and
whether the fragments were retained or not. A fragment was retained if it had a feature of interest
(such as a paw print or a tally mark, etc.) or was a particularly good example of its form or fabric.
Tracings at 1:1 were taken of all tegula flanges, flanged tile flanges, crested ridge tiles and tally
marks. All other fragments were fully recorded then discarded. Photographs were also taken of some
of the retained pieces. All the data was then transferred onto the Integrated Archaeological Database.
Roman forms
As no pre-10th century deposits were excavated on the site, and the site lay well outside the Roman
fortress, relatively little Roman material was present or expected. The Roman material accounted for
just 0.75% of the ceramic building material from the site and it was both very fragmentary and abraded.
The Roman CBM clearly represents a 'background noise' of residual material.
There were three fragments of tegula present. Tegula are rectangular roof tiles with a flange down
each side. The tiles were laid side by side on the roof, flanges upwards, and curved tiles called
imbrices were then placed above the adjoining flanges. No imbrices were present in the Walmgate
material. In addition to the tegula there was a part of a thick Roman brick, which was pierced by a
circular hole, presumably done to aid firing in the kiln. Apart from these four fragments all the
remaining material was so fragmentary it was impossible to tell if it was roofing material, walling
material or tile from hypocausts.
Medieval forms
The overwhelming bulk of the CBM recovered from the site was medieval and consisted of a variety of
forms of 11th16th century date.
The earliest form of medieval roofing tile consisted of curved and flanged tiles, which date from the
11th to the early 13th century (K. Hunter-Mann pers. comm. and Lewis 1987, 6). The curved
and flanged tile imitated earlier Roman roofing forms (tegula and imbrex) and is currently thought to
be associated with high-status buildings such as churches (Garside-Neville 1995, p33). As
there is no evidence for a high-status building directly on the site it seems more likely
that the material originated from a nearby church. Both the churches of St Denys' and St Margaret's
Walmgate were present in the 12th century and could represent the source for these fragments
(Wilson and Mee 1998, 73 and 98). There is a reasonable quantity of curved and flanged
tile on the site; some of the fragments are fairly well preserved and have various features of interest.
Two of the curved tiles had glaze on the upper surface; curved and flanged tile in York is normally
unglazed, though some glazed examples are known. One flanged tile seems to have had its flange knocked
off, possibly to enable re-use. A single example of flanged tile had a possible tally mark; tally marks
are thought to represent kiln batch loads.
A number of 13th16th century roofing forms were present on the site. Roofs during this time were
covered with flat tiles called plain tiles, and the ridges of the buildings were capped by ridge tiles,
which could be plain or decorated with crests.
Crested ridge tile was present on site, but never in large quantities. It was not always possible to
determine the shape of the crest due to damage, but ten examples were variants of fan shapes, which are
the most typical shapes for York (AY 10/05, 607). One of the crested tiles had finger-smoothing
parallel to the ridge, which was clearly decorative in nature (a feature that was also seen on some of
the peg and plain roof tiles). One crested ridge tile was clearly a kiln-waster as it was over-fired
and blown. Plain ridge tiles were far more common than crested types, accounting for 79.34% of all the
ridge tiles found on site. None of the plain or crested ridge tile was glazed.
Plain tiles could be fixed to the laths of the roof structure by means of a nail or peg inserted through
a hole in the tile, or by means of a projecting nib of clay. In general plain tiles in York were pegged
rather than nibbed, and had a single peg hole close to the top of the tile. Peg tile can be glazed,
often with splashed glaze, but is normally unglazed in York (Betts 1985, 378 and
AY 11/02, 295).
The CBM from the excavations accorded with this pattern. The bulk of the plain tile was clearly peg tile
with just three examples of nib tile present. The peg tile usually had a single hole, which was square,
circular or diamond-shaped. A couple of examples had holes that seem to have been pecked out after the
tile was fired. There were just two examples, both with circular peg holes, where the hole was so close
to a corner of the tile as to imply there were originally two peg holes on the tile rather than one. It
is, however, possible that the peg hole was simply off-centre as seen on examples from the Fishergate
excavations in York (AY 11/02, fig.144).
Some of the plain tiles had marks relating to their manufacture. These included tally marks, usually
located in the top corner of the tile, which may indicate kiln batch loads. Some of the tiles had
indented borders resulting from the tiler tapping down the edges to ensure both that the edges did not
stick up and that the clay filled the mould. Grip or finger marks caused when the tile had been lifted
while still wet were present on some tiles. A number of marks showed that the tiles were laid on the
ground to dry; these included grass or straw marks on the reverse of the tiles, and paw prints (cat and
dog) created by animals walking across the upper surface of the tiles. The most unusual example had a
baby's footprint in one corner of the tile. A small number of tiles had rain marks on the upper surface
so had clearly been subjected to a heavy rain-storm while drying on the ground. One of the tiles was a
kiln waster as it was over-fired and blown. Most of the tiles were undecorated; just two of the plain
tiles had dark green glaze on the upper surface. In addition a single plain tile had curious marks on
the upper surface that may have been stamp impressions. As mentioned above, a few of the tiles had
deliberate finger smoothing to create a ridged effect.
A small number of other 13th to 16th century roofing forms were recovered. These included two fragments
of possible valley tiles. Valley tiles occur at the junction of two roofs at 90 degrees to one another,
i.e. on 'L', 'T' or 'H' shaped buildings. In addition, there were seven examples of hip tiles. A hipped
roof is one where the ends of the building as well as the sides of the building have a sloping roof.
Specially shaped hip tiles are needed for the junctions of the sloping roofs.
A small quantity of plain glazed floor tile was recovered. Floor tiles of this type are of 14th16th
century date and are thought to have been imported from the Low Countries, though local manufacture
remains a possibility (AY 11/02, 299, 301). Plain glazed floor tiles could be square or
scored along the diagonal of a square then split to give a triangular shape. The tiles were either coated
in cream-coloured slip and then a clear glaze to give a yellow colour, or the glaze was applied directly
to the surface of the tile to give a dark green colour after firing. Many floor tiles seem to have been
placed on boards with four nails (one through each corner of the tile), presumably in order to trim the
tile to a standard size. The site produced examples of both square tiles with dark green glaze and triangular
tiles with cream slip and clear glaze. Nail holes were present on some of the fragments.
A large quantity of medieval brick was recovered from the site. Brick came into use from the 14th century
onwards, becoming more common through time. Medieval bricks are generally long and thin (rarely exceeding
50mm thick) and were usually made in sanded moulds, though some bricks were made in moulds dipped in water
(a technique called slop-moulding). In the case of this site just 18 of the medieval bricks were
slop-moulded. Some of the bricks had marks relating to their manufacture; many were similar to those seen
on the plain/peg tiles (grass or straw marks, rain drop impressions, paw prints, indented borders and
possible tally marks). A single brick had a turning mark on the base and one brick may have had slip on
the upper surface, but this was too abraded for certain identification. The most unusual of the medieval
bricks on site was from context 1747. It was a specially shaped brick that was possibly for use as
architectural detailing around a window. It is an unusual form and seems to have been painted, possibly
to imitate stonework. It probably dates to the 15th century or later and would certainly have come from
an important building (Garside-Neville in Macnab unpublished b, 137).
Much of the medieval material showed evidence for re-use in association with metalworking. Large numbers
of roof tiles in particular were covered with industrial concretion, iron slag or copper slag, or were
heavily sooted due to re-use in hearths/furnaces. This confirms other forms of evidence which clearly
suggest that metalworking was the principal craft activity on the site.
Post-medieval forms, 16th18th century
The post-medieval material from the site was largely brick. Most post-medieval brick in York was thicker,
shorter and narrower than medieval brick, and it was generally manufactured by slop-moulding. The bricks
on Walmgate largely conform to this pattern, though a few sanded bricks had with post-medieval dimensions.
Three of the bricks were of interest in that they were designed for architectural detailing; two were from
arches while a third had chamfers at the top and bottom of one stretcher implying it had been used as a
window mullion.
The remaining post-medieval material consisted of pan tile, which is of 17th century or later date, but
there was also a single fragment of a 17th century paving tile.
Modern forms
A small quantity of modern ceramic building material, including the remnants of a quarry-tile floor,
machine-produced bricks, wall tiles and sewer pipes was also found. The tile floor is of interest as the
tiles had maker's marks in the form of two crowns on the reverse.
Stone roof tile
A few stone roofing tiles were recovered. Stone tiles never formed a large proportion of the roofing
material in York, but they do occur on many sites in small numbers.
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Roman tegula from context 2115
Roman brick pierced by a firing hole from context 2638
Flanged tile from context 2936
Curved tile from contexts 2536 and 2852
Flanged tile with the flange knocked off from context 3120
Crested ridge tile from context 3118
Nib tile from context 2406
Peg tile from context 2682
Peg tile from context 2609
Plain tile with a pecked out peg hole from context 2343
Roofing tile with animal paw prints on the upper surface, from contexts 4012, 3090, 2145 and 2101
Plain tile with a baby's footpint from context 1492
Over-fired and blown tile from context 2539
Cross-sectional view of over-fired and blown tile from context 2539
Tile with finger smoothing from context 2218
Valley tile from context 2322
Hip tiles from contexts 2392 and 2852
Triangular floor tiles from context 1346
Detail of nail hole on floor tile from context 1346
Elaborately moulded medieval brick from context 1747
Tile covered with copper alloy from context 1910
Elaborately moulded post-medieval brick from context 1612
Reverse of a modern floor tile showing maker's stamp from context 1201
Detail of maker's stamp from context 1201
Stone roof tile from context 1870
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