Detailed assessment of the Spire and Tower condition

 

Although the church diligently carries out maintenance and
repair work there are a number of issues with St Mary’s
Church.

 


The issues relating to the spire highlighted in the last inspection
report have been investigated at high level by a steeplejack
and advice has been sought from a conservation accredited
structural engineer. There is movement of the upper portion
of the spire, possibly related to iron cramps embedded in the
stonework. The engineer’s recommendation is that a stainless
steel holding down rod and cross tree are installed, which will
require the taking down and rebuilding of the upper portion of
the spire. There are also issues with stonework deterioration,
particularly to the lucarnes, and the pointing to the upper
portion of the spire. There are also localised stonework and
pointing issues to the upper portion of the tower. Water is penetrating the spire through the stonework in a number of places as well as through the lucarnes, where the detailing of the fabric to the rear of the louvres means that intercepted water is discharged down the internal face of the spire walls.


The tower roof gutters between the parapet walls and the spire are lined with lead, which is in a very poor condition. The roof outlets at the corners of the spire are significantly under-sized and are highly vulnerable to blockage by small amounts of debris. There are strong indications within the tower that these gutters are leaking.


The valley gutters to both the north and south aisles do not have an adequate fall to the outlets with water pooling in both gutters. There is a similar lack of an adequate fall to the outlets of the narthex roof, although the covering currently appears to be in a good condition. There are also maintenance issues with the asphalt lining of the north aisle valley gutter at its eastern outlet and slipped slates to the south slope of the south aisle, which both need to be addressed.


The areas of the cement rich pointing to the rubble stone elements of external walls are deteriorating. This is particularly evident to the south aisle, although this appears to be a generalised problem. Although the situation is relatively minor at this stage it is likely that repointing will be required to these areas within the next ten years.


Despite all the issues above the interior of the church is well maintained and in a very good condition.
 

Roofs, Parapets and Gutters
Spire
i The spire is of ashlar stonework and is formed with eight facets. At the base of the NE, SE, SW, and NW facets a low broach detail resolves the base of the spire to fit the square plan of the tower, which is not visible from ground level. There are two distinct changes of slope of the spire; the first at the upper lucarne level and the second which appears to mark the transition where the stonework becomes solid towards the top of the spire.
These possibly reflect historic rebuilding. There are lucarnes at one thirds height on the cardinal faces of the spire and lucarnes on the NE, SE, SW, and NW faces at two thirds height. The spire is capped by a weather vane.

ii The north facet lower portion of pointing is in a reasonable condition, there is limited deterioration of individual stones caused by pocketing in the limestone. At high level pointing deterioration is evident. The stonework of the two-light gabled lucarne is in a reasonable condition, although the head of the surround of the western lucarne opening has displaced approximately 15mm and should be re-bedded or repointed as part of any future work to the spire. The gabled head of the
lucarne appears to have deteriorated and is in need of repair. The spire above is difficult to see but from ground level evidence of pointing deterioration is visible below the upper solid section
of the spire. A steeplejack’s inspection has shown movement of the upper portion of the spire, possibly due to the corrosion of iron cramps embedded in the stonework. A structural engineer has recommended the insertion of a stainless steel holding down rod and cross-tree as part of works to stabilise the upper portion of the spire.


iii The northeast facet has a single high-level lucarne opening, which has a single light with crocketed mouldings to its gabled head. From below this appears to be in a reasonable condition. The pointing of the stonework of the northeast face is in a generally good condition, although there is localised deterioration at low to medium level. The upper portion of the spire is more difficult to see due to the change in pitch of the spire above the upper lucarne, although from ground level this appears to be in a reasonable condition. The base of this facet has a broached corner, which is in a good condition.


iv The east facet stonework is in a reasonable condition at low level. The two-light lucarne is in a reasonable condition, although there is a displacement of 10-12 mm between the head of the opening from the surrounds of opening which requires repointing. Viewed from below the crocketed gabled head of the lucarne appears to be in a reasonable condition although a vantage point which provides a good view is not available. The condition
of the upper portion of the tower is not clear due to the change of slope around the height of the upper lucarne, although the previous quinquennial inspection report and a report by a steeplejack indicates that there is significant deterioration in this area.


v The south east facet single light opening from below seems to be in a reasonable condition. The facet is in a generally good condition, although there is localised pointing decay and localised deterioration of individual stones. The base of the facet has a broach at the corner, which is in a good condition.


vi The south facet of the spire has a single two-light lucarne at low-level. There is a significant amount of mortar decay to this facet up to a height of the neighbouring upper lucarnes and a number of the joints appear dry, which requires urgent repointing. There is slight staining due to the wash-off of the copper down tape of the lightning conductor, which is attached to the angle between the south and the south west facets. From below again this appears to be in a good condition. There is a door opening from the interior of the tower with a vertically boarded timber door, which is in a good condition.


vii The southwest facet stonework is in a generally good condition up to the upper lucarne level. The condition of the lucarne is not clear from this vantage point. There are open mortar joints, between the two lucarne levels. The upper portion of the spire condition is not clear. The broach at the base of the spire is in a good condition.


viii The west facet of the spire stonework is in a reasonable condition at low-level. There is pointing deterioration immediately below the lower lucarne and between the lower and upper lucarnes, which need to be repointed. The condition of the upper portion of the tower is not clear from this level, although the previous quinquennial inspection report and a report by a steeplejack indicate that there are structural issues at higher level. A structural engineer has recommended that a holding down rod and cross tree should be installed to stabilise the upper portion of the spire.


ix The north west facet of the spire stonework is in a generally good condition and again there is local minor deterioration of the pointing, chiefly at higher level. The broach at the base of
the spire is in a reasonable condition.


Tower Parapet Gutters/Roof
i The valley gutter between the spire and the parapet to the north gutter is formed in 2 sections joined by a hollow-cored roll. The gutter discharges into the gutters on the east & west sides of the
spire. The leadwork is heavily deformed and pitted and the roll between the 2 sections has been trodden flat. Water is held in a number of places, most severely at the step down into the east
gutter where 12mm of water is held due to the deformation of the leadwork. The abutment flashing to the spire is in place but has ripped in a number of places, chiefly the northwest corner and at the centre of the wall. The pointing holding the flashing in is loose or missing in a number of places. The abutment flashing to the north parapet wall is in place and the pointing is in a generally good condition, although portions of the flashing are not dressed sufficiently into the wall to provide
a weathertight seal. It is recommended that the gutter lining and associated flashings should be replaced.


ii The lead-lined east parapet gutter is formed in 2 sections. The gutter lining is deformed for its entire length but appears to be on a solid base. The roll between the two sections of the gutter
has been flattened and is in a poor condition. This outlets in the northeast & southeast corners. The diameter of these outlets is about 50mm, which is not sufficient to guarantee water escapes adequately and is highly susceptible to blockage. The southeast outlet discharges via a cast iron hopper into a cast iron downpipe, which is running clearly. The northeast hopper
chute extends over the remnants of a gargoyle. Beyond the gargoyle the chute has deformed so that it no longer throws water clear of the tower. The abutment flashing to the spire has sections where it is loose or the pointing to the spire is missing. The flashing is poorly formed, and it is recommended that this is replaced. The abutment flashing to the east parapet wall is in place but again is poorly formed and is ripped in a number of places. The flashing is only dressed approximately 10mm into the wall, which is not sufficient to provide a weathertight seal. It is recommended that this is replaced.


iii The south gutter is formed in two sections. The roll joint between the two sections is almost completely flat and the gutter base is deformed significantly and is holding 10-15mm of
water in a number of places where there isn’t an adequate fall to the and the outlets. The pointing to the abutment flashing to the spire is missing in a number of places and requires repointing.
The flashing to the south parapet wall is only dressed 15mm into the wall, again the sections of the pointing are missing. Sections of the flashing have deflected and are no longer fulfilling
a useful role.


iv The west parapet gutter is formed in two sections. The base of the gutter is heavily deformed and there are areas where up to 10mm of water is held. It is not clear whether there are any tears in any of the gutter linings due to the weather, although at least 1 lead welded repair has been made in the past. This gutter discharges via 50mm diameter openings in the southwest and northwest corners. The southwest outlet appears to be prone to blockage as debris has built-up in the 2 months since
the last visit. This discharges via a lead chute outlet that is heavily deformed. The northwest outlet is a simply formed lead chute, which is heavily deformed and is partially supported by a wrought iron support bracket, although the bracket, or the chute, has moved slightly and is no longer providing much support. The abutment flashing to the spire, although poorly formed, has pointing that is in place but is slightly loose to its southern end. Approximately 1.5 linear metres should be repointed. The abutment flashing to the west parapet wall is in place and is formed in sections that are approximately twice as long than current recommendations. There is a tear in this flashing but at the current time it appears to be fulfilling its purpose.


Tower Parapet Walls
i The north parapet wall is capped with crenelated copings and has corner finials with crocketed caps. The northwest finial is in a reasonable condition and the pointing and stonework are in place at least on the inner face. The inner face of the parapet wall exhibits minor erosion of the pointing and minor spalling of the inner face of the stonework but is otherwise in a good condition. The northeast finial stonework is in a generally good condition.


ii The east parapet wall is crenelated. Apart from minor deterioration of the pointing the inner face of the wall is in a good condition.

iii The southeast finial is in a generally good condition although there is minor deterioration of the pointing.


iv There is loose pointing at the abutment of the south wall with the southeast finial, which should be replaced. There is further minor deterioration to a number of joints of the inner face of the wall which should also be repointed. (approx 1 lin m). The lightning conductor down tape passes through the south parapet wall towards its southwest corner and passes through a mortar joint.


v The stonework to the top of the octagonal base of the shaft of the south west finial is quite heavily eroded. Thefaces of the stonework have eroded by up to 50mm and ideally this upper stone should be replaced. The finial above is in a reasonable condition.


vi The is minor spalling of the inner face of the stonework and pointing of the west parapet wall which should be defrassed and repointed to ensure that the stonework is weathered. (Approx
1.5m2)