|
A rough stone base links this 1913 bungalow to its rocky upland site
|
When I said ‘yes’ to buying an old house
built on a stone
foundation, I had no idea of the new headaches I was agreeing to as a
result. We tend to see things made of stone as permanent (part of
their charm) whereas materials like wood we more easily accept need
periodic maintenance. But stone needs attention too, only over much
longer intervals if it's been well done originally. And
as many do with houses, I went for the whole enchilada without closely
examining all the
parts, then gradually awoke to the realities of the work needed in order to
stabilize and repair the building.
As I settled into my new home, I began
noticing among other things that its sturdy stone base in fact sported several breaches. It turns out that seventy-five
years of exposure to weather with minimal maintenance
will do that to a foundation held together by mortar. The materials
comprising it were ordinary, mostly collected on site, and randomly
set without conscious patterning or coursing. A lot of
different shapes and sizes of stone had gone into that foundation, with a
crazy-quilt of seams as a result. Here and there enlarging cracks offered
openings to the shallow crawl space behind them. Earth shifting,
courtesy of forces like tree root expansion or earthquake tremors, plus
the effects of freeze-thaw cycles, can crack and degrade
even sturdy walls over time. In some spots the base of the wall was
actually coming unstuck and starting to dilapidate.
|
As roots grow and expand, they raise the soil and easily crack rock walls
|
|
A section of wall broken by expanding roots, needing attention
|
I also began
noticing signs of slapdash fix-ups, careless work that had simply
smeared mortar across the face of the stone. These sloppy repairs (what
the English call 'bodges') leapt to the eye like carbuncles. So of course
my first thought as a naieve homeowner was to involve someone more skilled
(‘call the plumber!’) to address the problem.
But back then I didn’t know anything
about stone
masonry, so I talked a bricklayer I’d hired to fix some spalling chimney bricks
into patching an area on the south wall. I simply assumed the skills
required were one and the same. He was a bit disinclined, a cue I should
have taken, but then agreed. Once his patching was done, I completely
got his hesitation. In contrast to the neat bands of mortar he placed
so precisely between
the courses of the bricks, his approach to stone involved smearing
mortar
across the joints. I’m unsure why irregularity of form should cause that
response in a
bricklayer, but the results were unfortunate for the look of the
foundation. Later, I spent a few hours chipping away the worst of
the smeared cement, to make the joints recede in emphasis and restore something like
the original look.
|
Mortar smeared across the seams obscures the look of a stone wall
|
|
A section of rubble stone foundation wall whose base has been rebuilt
|
While watching the bricklayer go at this
work, I realized how
ungainly his attempts to get the mortar into these wandering seams
actually
were. Using a pointed mason’s trowel for the carry and a smaller one to
push
mortar into the seams simply didn’t cut it. A pointed trowel may be a great
tool for
dressing a brick before placing it, but for infilling irregular seams in
a
rubble stone wall it clearly wasn’t working. The outcome argued against
continuing down this path. The
thought dawned that I myself needed to learn how this type of work
should be done, so I could avoid further damage to the look of the building. I don’t know why
I opted to get personally involved rather than just finding a skilled
stone mason,
yet it was but a small step from there to working directly with
stone.
|
Ongoing repair: buttress needing attention
|
A stone base under a house creates a
distinctive impression, gluing the building firmly to its site in a
particular way. If the rock used is taken from the site itself and the
building sits on bedrock, the house feels at-one with the
landscape. But let that look become marred by walls entombed in
concrete and the stone is thereby demoted to an indistinct element in a matrix,
causing the original
aesthetic to recede. Taken far enough, it disappears entirely. You may
as well have a
full concrete foundation as have rocks masked by mortar. I thought it
important not to go any further down that path.
|
Seams slathered in mortar for a messy outcome
|
So that's when I naievely began
what is now twenty-five years of working with stone and mortar to repair
and make things. I wasn't inclined to DIY by nature, had no skill at all when I
began, but was intrigued by the
medium and resolved about its importance in maintaining the heritage
asset. And I was a gardener, so had some limited experience making loose rockery
walls to retain beds, with an inclination to pile rocks together as a
result. I decided to begin by tackling the
most visible breach first, upping the ante considerably. It appeared at
the centre
of a low wall between two tall battered piers supporting the house’s
most prominent feature – an elegant entry verandah that one walks by on
route to
the front door. It appeared that a few weaker chunks of rock had popped
apart, causing
a crack to appear.
|
My first job site: a serious breach in the low wall between the piers
|
I hadn’t a clue how to go about making a
repair, so I began by
observing some of the masonry work in progress around the region, which
was mostly of the low stone wall type. Here in Victoria rock is always
breaking through the landscape, dotting it with outcrops and
larger hills not fully covered with vegetation. Bedrock breaking through
the landscape defines dramatic contours, and loose rock on the surface
seems to prompt a lot of boundary marking with stone walls. And because
this material is local and often not much worked before using, the
results often feel natural and fit for their surroundings.
|
A small knob of glaciated bedrock protruding through the ground
|
|
Rocky outcrops define a landscape with oaks, firs and arbutus groves
|
|
Regional character: rock outcrops, Garry Oaks, boundary walls
|
The operations I
observed and the masons I chatted with all used mortar made from
scratch, combining
sand, cement and water in mechanical mixers to produce large batches at a
time. My
first problem was that none of this apparatus would fit in at my site,
which had
no place to store and mix sand and cement that would not have been an
eyesore
and in the way. Nor were industrial quantities of mortar actually needed
for the
relatively small and picky repair work I’d be attempting. How to access
mortar in small quantities was an initial obstacle to getting started.
|
Bodged work stands out, doesn't last
|
Things stalled there for a while, until
the puzzle of making mortar solved itself with the discovery that it
came pre-mixed in 25-kilo bags – not exactly a blinding insight, but
until you know
of the possibility, it doesn't exist. I learned about it purely by chance, in a
buddy’s back
garden, when he enthusiastically shared his rather exuberant approach to
building a low retaining
wall. I watched fascinated as he whipped up a small batch of bagged mortar in a
plastic
pail (‘just add water and stir’), then proceeded to use another one of
those pointed
trowels to rather awkwardly place it. It was a eureka-moment - here was a
way to make mortar that was manageable for repairs.
If sourcing mortar is essential, it’s
also necessary to
have tools suited to the work of mixing it up and placing it without
undue mess. There things stayed
murky a while longer. To repair an existing wall, you need a way of
transferring small quantities of mortar to niches of varying size. This
is
quite picky work. And moist mortar is prone to sliding on metal, a bit
unpredictably. And you need to place it with enough precision, in
awkward spaces and at odd angles, to avoid marring the face of your stones.
Otherwise, you risk the look of entombment, which is pointless and
inartistic.
|
Successive bodges mar this stone wall, which even drains aren't saving
|
|
Stone retreating behind mortar, now imprisoned in concrete
|
As I began preparing the breach for
repair, I anxiously watched the opening enlarge beyond the apparent
problem and the scale of the job increase in tandem. I'd improvised a
partial solution
to the transfer problem by selecting a compact drywall knife in
preference to a
trowel. Initially I chose it just to mix up the mortar in a pail – its
continuing
utility evolved naturally from there. A compact blade offers a
horizontal platform
from which small quantities of mortar can be eased into seams. I am still using Quebec-made Richard knives to this day,
both for repair and for new construction.
|
Impractical mason's trowel above, useful Richard knife below
|
Yet another tool was needed in order to
transfer the mortar from the
knife to the seam and to work it into place. One day, watching a city
worker setting
stones in a piece of sidewalk art, I noticed he was
using a table knife to fill and dress the openings. He allowed that he’d
‘borrowed’
it many years back from his wife, but hadn't ever returned it. He used
its narrow blade deftly to work the outside of the seam, so the mortar
stayed within the lines and even had a bit of a finished look to
it.
Intrigued, I borrowed an older knife
from my own kitchen, a strong
but thin steel blade with a bit of ‘give’ to it. The combination of
firmness
and give enables a surface tension that’s useful in working mortar into
crevices. It mimics the design of a mason’s pointing tool, which has a
similar
spring or tension to it. I soon realized I would need to get mortar into
spaces too tight for the width of the knife's blade, so I
also acquired several of the pointing tools used by masons (I'm still
mystified why the
mason I originally hired opted not to use pointing tools to push mortar into the seams!).
|
Basic tools: kitchen knife (right), Richard knife, four tuck pointers
|
While I was still stymied by the
challenge
of making mortar, I bravely allowed myself to start the job by removing
the defective
pieces. This phase of repair typically establishes the real scope of a
project, as loose
material behind the breach comes to light. Here it revealed the presence
of a
brick pier, obviously meant to support the verandah floor in the
vertical plane
but now tilting alarmingly due to brick disintegrating where it
contacted wet ground. Evidently it was the movement of the pier that had
caused the wall to crack and come apart. This new problem caused me
some anxiety about proceeding at my skill level, but I decided it was
better to know about it and attempt a repair than to
neglect it and soon cause a bigger problem. I was also realizing I'd
have to replace some
rocks that had actually broken apart, and that compatible materials
needed to be found.
|
Securing the brick pier before fixing the wall
|
Getting to the point of mortaring
anything took a very long
time, but a logic for placement emerged once I located some suitable
stone
and dry-fitted it as best I could. A skilled stone mason would be able
to visualize an outcome
without needing to mock it up, but as a beginner I needed to see in
advance as
best I could. The trick lies in finding material that mates well with
what is already in place, so the patch doesn't call attention to
itself. Here the challenge was to fill up the opening as much as
possible with a single piece while maintaining a vertical alignment
consistent with the rest of the wall. And then to place it and seal it
as though it had always been there, leaving no blatant traces of repair.
It complicated matters that in this location the bedrock dipped
somewhat.
|
Candidate replacement stone being positioned for fit
|
There was a lot of loose rock lying
about the place, but
nothing that felt right for the opening I was dealing with. So I began
scouring
highway cuts and old excavations looking for local materials, which back
then could
more readily be found. Finding useable material is part of every job,
and
compatibility is always an issue when working on an existing structure
and striving for seamless repair. Nothing
shouts 'bodge' like stark contrasts in materials – unless it’s sloppily
applied
mortar. My first structure was well-weathered at seventy-five years of
age, made of local stone of various colours and textures – the opposite
of ‘green’
stone of uniform colour. Mating new and old was a challenge that had to
be met with careful selection.
|
Many years later the repair doesn't stand out unduly
|
|
Replacement stone is broadly compatible with the original rocks
|
Eventually I found what I thought was a
suitable piece for
the biggest opening, then assembled a supporting cast of smaller pieces
to fill gaps to neighbouring stones as well as other crannies in the
wall. It took a painfully long
time to complete this small project, a result of proceeding slowly with
awkward hands learning to slide mortar carefully into place (a moving
target
that) and then smooth it to a uniform face. A comparable
awkwardness might be the one a boy experiences when first trying to
guide a razor over the contours of the face. The kitchen knife however
quickly proved invaluable, and in time a
rudimentary process for transferring mortar also evolved. The trick was
keeping it where wanted despite gravity-fueled tendencies to travel
where it wasn't. I kept a wet sponge and toothbrush handy for cleaning
sloppage from the stones. Vertical seams
are bedeviling, even to this day. A special tool for vertical placement
is an obvious gap in the repairer's tool bag.
|
Massive stone pier also needing base repair
|
When finally completed, this first
project gave me a sense of satisfaction far beyond the modest scope of
the work. I felt I’d opened a door to the world of stone building and
won some knowledge through the execution of the work, despite offending
many
rules I was then totally unaware of. And while my hands would be busy
with
restorative projects indefinitely, completing just one prompted me to
wonder what
it would be like to make something from scratch. That experience actually lay
close to hand: while passing many an hour staring at my repair's slow
progress, I'd also noticed that the
massive uprights supporting the verandah roof were beginning to come
unglued at the
base. While one of these could be repaired as was, my
intuitive feeling was that the other needed a foot, or plinth, added to
truly secure it. It appeared that there was a brick support at the heart
of the stone pier, and that as with the wall, the bricks were spalling
where the base sat on moist rock.
Looking back on it, this was a very big
leap for a newbie.
The implications were potentially large, because I was about to modify
an original design that was substantially intact. Indeed, aesthetically
and from a distance, it wasn't at all evident that anything needed to be
done. But looked at closely and carefully, it was obvious that it did
or else risk the integrity of the original column down the road. And I knew I
wasn't capable of rebuilding that pier to its current standard. So I
decided I would proceed by laying out the design for a base completely
before placing any stone permanently –
and only go ahead when I was satisfied it would be aesthetically
compatible. This was a brave step along the
problem-finding/problem-solving continuum.
|
Making the plinth to feel it was always there
|
This second job led to more searching
for appropriate
materials that fit the existing composition. It was only a minor amount
of new construction, but visually it had
to be right and so it too advanced at a glacial pace. As compatibility
was imperative, I studied the shape of the existing construction and the
way the rocks had been put together for a subtly rustic effect.
Eventually, by endless playing around, I got what I thought was a
goodish look, meaning one that
didn't stand out as incongruous or arbitrary. And with my evolving
skill in
placing mortar, the job moved slowly but steadily forward in execution
(new construction is far easier than repair for managing the mortar).
When I look back on this small yet prominent project,
I’m amazed I tackled it with so little experience. In effect, this
repair is
what launched me on the path of new building with stone. Looking at it
twenty five years on, I take satisfaction from the fact that the eye
doesn't notice anything amiss, that what was an original artistic
ensemble before my hand was on it, remains one after.
|
Weathering elements like powder lichen help the plinth blend in
|
Down the line there were many such
repairs (and still are) plus
a whole lot of stacked garden walls between me and the next bit of
new mortared construction. But my choice to tackle repair myself had
launched me on a path that continues to elaborate itself 25 years on. I
haven't become a stone mason by any means, and it's certainly too late to
acquire true journeyman's skills in any systematic way, but my skills
have developed in the ways needed to do the jobs of repair and addition
required in my own milieu. And using those skills has become an
increasingly expressive act that continues to hold my imagination.
Dedication: this piece is
affectionately dedicated to my too-early-departed friend Dennis McGann, a
hugely talented designer, communicator, and artist
who, among many
important things, inadvertently turned me on to bagged mortar. Dennis
respected and cultivated craft in all his doings and equality in all his
dealings with people. He was a fine person who is sorely missed.
No comments:
Post a Comment