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Cracks in cob walls

Typical Problems in Cob buildings - A1 Complete Builder

Cob Building - How to prevent cracking cob walls - YouTub

However, if the cob is cracked or soft or contains too many stones to hold itself together, the whole wall could collapse above the doorway. It sounds like there is a lot of weight up there! In that case you would want to slowly carve away the wall at the level of the new lintel and stabilize it as you go, which would be quite tricky Using some pressure and a paint knife, press the compound into the area. After it has time to dry, scrape off any bumps with a pass or two of the knife. When the first coat is smooth, add a second coat in the same way. After the second coat is dry, add a third and final coat while ensuring no lumps or bumps. 5 Use a mix of cob and manour to get rid of cracks in your cob wall. Rain, frost, dry pieces of clay, anything can ruin your once perfect mancave wall. Use a r.. Movement in a gable wall can be a problem if the crack widens significantly as it goes up the wall. Unfortunately modern cement renders, plasters, masonry paints and emulsions conspire to trap moisture in the wall and damp cob can lead to structural problems. Once the moisture level exceeds 12% the strength of the cob drops dramatically Cracks in walls are a perfect example of this. Houses are always moving, even new builds. This could be due to settling, which you find with all new homes, movements in the soil under the house, or changing humidity levels (amongst other things). When this happens, cracks can appear in drywall, plaster or concrete

Occasionally the wall may move to the point where it will need touching up with the wall colour but the crack will stay hidden.´ AND (2) ´As an interior designer, we used quite a few of the Rondo jointing profiles/strips, one of which is used to join two walls, allowing for future independent movement We're new to cob and took it upon ourselves to make a modest cob structure this summer- erecting cob walls around a pre-existing covered patio beside a garage. All was going smoothly; we had figured out the perfect ratio of native soil to amendments (clay powder, in our case) based on multiple test bricks and shake tests, and had a solid 18 inch urbanite stem wall over nearly a foot of gravel

Whether drywall, plaster, or concrete, walls are susceptible to cracks.Even walls in newly-built homes are prone to cracks, which normally occur from settling. Homes are constantly settling as different construction materials expand and contract at different rates Ken Kern, the pioneer of owner-building in the 60's and 70's, died in an experimental earthen dome that he built and plastered with concrete stucco. He was sleeping in it the night of a huge rainstorm, when enough water finally got through the cracks in the plaster and into the cob walls to snap the concrete structural reinforcements

Cob Walls As a guide, if you have excessive or large visible cracks to the render, you should expect a number of cob repairs. Whilst it is straightforward to give a cost for lime rendering per square metre, it can be difficult to provide a quotation for remedial cob work. Generally Earthouse advises customers to allow a 15-20% contingency for cob repairs. Build the walls. Once you have your cob mixed, you can use it to form your walls. To make walls, you should form lumps with the cob and add a handful at a time, smoothing it out as you go. Avoid slapping on the cob as this will draw moisture out of the walls, and you want it to cure naturally. As you work, do your best to keep the walls. Cob is very resistant to weathering. Because of its porous nature, it withstands long periods of rain without weakening. However, too much exposure is best avoided by the boots and cap strategy: wide roof eaves to protect the walls and an impervious foundation. In windy areas a lime-sand plaster is traditionally used to protect exterior cob.

Should You Worry About Cracked Render on an Old Cob or

The sticks will be buried in the new cob when you continue building. Patching an already dried wall . Plaster adheres beautifully to cob and will cover minor dips and smooth out the overall contours of the walls. But if you want to make a more major change and add new cob to the old, start by wetting the dry cob as much as possible If you want to preserve specific cob walls against wind-driven rain, snow and wash-outs, you can use boiled linseed oil to coat it your wall. WARNING: do not.. Cob is a term often used to describe the clay and straw mixes mainly found in West Country. In the Wessex region the traditional cob is made of chalk sometimes with or without the addition of straw. The chalk being the aggregate and binder in one. Chalk cob walls can range in colour from almost pure white to a muddy brown

How to seal a cracked masonry foundation wall or floor slab.Typical concrete crack preparation for sealant with an epoxy product. Use of Polyurea as a control joint filler or crack sealant in concrete slabs (Polyurethane Foam Injection Method). Use of Epoxy-supported Grouts as a control joint or crack filler in concrete slabs or walls A thin lime and chalk render is sometimes added if required. Small holes are filled with the chalk cob alone. Cracks in the cob are often pinned using helifix ties and then filled with the chalk cob. Cob walls that are to be rendered are repaired in a similar way. Sometimes some lime is added to the bedding in mortar Score the Crack . Use a utility knife or painter's 5-in-1 tool to cut along the edges of the crack, opening up the crack slightly and removing loose material. While opening the crack may seem counterintuitive, you need to increase the area for the joint compound to stick. Do not vigorously scrape into the crack; be gentle and go slow

This makes cob house one of the safest DIY homes that one can go for. # Sound insulation. When one talks of acoustic insulation, cob houses are right up there among the best. Walls made from earthen material has excellent sound-absorbing properties which keep the outside noises subdued to a great extent and vice-versa Typically, cob walls are plastered with mud mixed with straw, though in poorer homes they were left un-plastered, with mud slurry and lime wash as crack fillers. If we walk into an old house with.

Mar 18, 2014. 206. 0. Jun 9, 2014. #1. Hey all I'm a little worried about my corn cob pipe,I've started noticing cracks in the seams between where the kernels were connected to the cob. I've fiddled with the pipe and it still feels sturdy but the cracks are still a little disconcerting.My pipe is the Missouri Meerschaum Eaton I believe You can almost certainly patch your existing walls by adding more cob as a thick plaster to even out the walls and cover over the cracks. However, this will not address the structural issues if you have major cracks in the wall, so it is not an ideal solution. Q: I am from India The storage capacity has to do with weight. If volume is an issue, go with solid masonry or cob. Bottle walls can allow light to enter the space. A light blocking blind, would block the light, so that it would be converted to heat. The addition of glass, allows a cold wall to immediately allow light and heat to enter the space,early in the morning Cob homes are one of the most durable types of earth architecture. Because the mud mixture is porous, cob can withstand long periods of rain without weakening. A plaster made of lime and sand may be used to windproof the exterior walls from wind damage (Michael, 2000) Other wall and ceiling cracks probably run in more-or-less straight lines--almost as if someone had planned them that way. These cracks are usually caused by seasonal changes in humidity, which creates stress points in the plaster as the framing lumber in your walls expands or contracts as it takes on (or gives up) moisture from the air

Home Foundation Cracks If your home's foundation suffers from cracks wider than 1/4 inch or displays stair-step cracks, it may need repair, commonly through injected epoxy resin If your walls have formed cracks, chips, or holes and you need to have them repaired, judging the cost can be difficult. To give you an idea, homeowners spend an average of $753 per repair.Most projects will fall between $357 and $1,173 Cracks appear when the sand:clay mixture dries out and contracts. If you mistakenly use clay only to build your oven layer you will see significant cracks appear. You should not do that! However, you can get major cracks, even if you use the correct mixture of clay and sand. This happens if the oven dries out too quickly Grouting of cracks in earthen test specimens. The developed grout formulation was tested on earthen specimens consisting of cob wall panels. Cob was produced by mixing earth with straw and water to a plastic mass [3]. The cob mass was then thrown diagonally onto a larger heap of approximately 110 × 80 × 70 cm Cob: The thick cob walled houses in the West Country are probably the best known of all earth walled building types. Their thick walls are made by piling a mixture of subsoil and straw, about 600mm thick, on the wall and paring the rough edges flush with the wall. The next layer is put on when the previous work has dried enough to bear the weight

Selecting Soil for Cob and Testing Your Cob Mix - This Cob

  1. Over time and with repeated use, a cob oven's outer plaster layer will likely need to be touched up as cracks form on its surface. Such cracks are due to a combination of weather and the expansion and contraction that naturally occurs when a material heats from a low temperature to upwards of 1,000°F in just a few hours
  2. The old thick walls of cob, brick stone or rubble infill were designed to 'breath' excessive moisture out by capillary action. Cob Buildings were the normal method of construction for most buildings from the 15th century and went on until the end of the 1800s when it was widely replaced by brick, although it has seen a revival in recent years.
  3. Cracked, broken, loose or blocked guttering is one of the most common causes of water seeping into the cob walls; it pays to check your gutters and make sure they are cleaned and cleared regularly. Thatched roof houses do not usually have guttering so make sure there is an alternative way to drain excess water away from the house

THE SOLUTION: REPAIR CRACKS. Stuff flexible backer rod such as SOF rod into the check up to about 3/8″ from the surface. Consider using painter's tape to mask off the surface of the log to prevent caulking from smearing onto the surface of the log, creating a mess to clean up The other gable end wall is completely covered in 1-2inch thick concrete/pebble render - - which presumably encases the old cob-wall and strengthens it (though it could be brick behind it). Like the other end a window has been placed on the first floor - -and similarly the wall above it is just 2 inches thick The expanded ties can jack up the wall, resulting in horizontal cracks at periodic mortar joints corresponding to the tie positions. This is usually more evident to upper walls. Doors and Windows It is very common to find stepped cracks above openings in cavity walls where the doors or windows have been replaced, too. This is fairly common in. Hairline cracks are not a problem in themselves as long as the render is still firmly applied to the wall. Cracking may occur around the edges of old patch repairs. This is often due to the patch being made with mortar that did not match the existing. Check for plant growth in walls and staining caused by leaking gutters, downpipes or overflows

Cracking cob (cob forum at permies

  1. A wattle and daub wall breathes, and so, like a bale or cob wall, helps to create that most pleasant living environment familiar to anyone who has spent time in a natural building. NB: for these reasons, it's important not to use impervious materials like cement or non-breathable fillers or paints
  2. • Cob therefore lends itself to organic shapes: curved walls, arches and vaults. • Building with cob is a sensory and aesthetic experience like sculpting • ADOBE • COB Water Proof • Cob is very resistant to weathering and can withstand long periods of rain without weakening
  3. tend to form hair cracks as they set: these are hardly visible to the eye, but moisture enters the wall by capillary action. Once in the wall, Figure 5: Strong cement render on a cob wall. The render is being forced off the wall and is taking the surface of the cob . with it. The cob behind this is decaying. Photo: Philip Hughe
  4. Micro-cracks will heal itself by salt in the air crystallizing in it and CO 2 being absorbed until complete curing. Combined with the longer curing time this makes lime an ideal mortar for foundations supporting earthen walls like Cob/Adobe. This allows plastering while the walls are not fully dried yet and still settles when the roof goes on

Plastering and Waterproofing Co

  1. I figure that if any cob wears off due to weathering, I can always add more in the spring. I took a quick look yesterday and didn't see any cracking in the base, or expansion of the cracks in the cob walls. I'll take a level out this weekend and also take a good look at the interior. anonymous on April 04, 2013
  2. The role of fibres inside cob walls was to (1) facilitate the mixing , since no structural damage cracks should propagate inside cob walls . Considering that raw materials were natural and locally sourced, cob masons had to do with available materials. Earth type was the major constraint that dictated construction strategy (particle size.
  3. Clay/cob walls can be burnished with a smooth metal object (like a big spoon) to a very smooth shiny finish, and then oiled to resist water. That's all the info I've got in that dept. Very interesting. Maybe gleying walls is more for hardness and smoothness than waterproofing. I am very interested in appropriate technologies so will keep looking

Small cracks are no big deal. You can patch them with adobe or just plaster over them. Larger cracks that keep growing are a sign of a more serious, structural problem (like the wall is leaning). You can use adobe for almost every part of your house - walls, floors, even roof when using bricks Ants in the Walls. Depending upon distribution and cold weather conditions, ants may be as likely to nest outdoors as indoors, especially in many parts of the warmer, more southerly portions of their distribution.Also, the preferred indoors locations and food preferences of the ants listed below may vary to some degree since there is a lot of species-specific variability among ants Cob in Cornwall - The Cob Specialist. Leslie Cornell Snr - the most trusted Cob Wall Specialist in Cornwall - has over 20 years of experience with cob building techniques that includes repairs, builds, lime rendering and pointing. Les Cornell Senior is based in St. Austell, Cornwall and performs cob wall surveys and is trusted and well known.

Cracks in the masonry wall or poor tuckpointing have allowed water to get behind masonry wall. Repair and Prevention If moisture is getting into the masonry wall, eliminate the source of moisture by properly tuckpointing any cracks or missing mortar in the wall or patching concrete with a latex concrete patch; clean out gutters and downspouts. The cob wall cottage in Bow near Crediton collapsed at 2:26pm on Saturday, February 17, just six minutes after the quake which had an epicentre 185 miles away north of Swansea in Wales The majority of our work is the high quality repair of historic buildings, homes and walls, particularly those containing cob. Whilst we mainly work within Devon, we are happy to be involved in work further afield and indeed around the world! Repairing Cob. Cob is a remarkably durable material provided it is treated correctly

Structural Considerations for Cob Building

  1. This will cover hairline cracks which allow moisture to get behind the harling causing it to break off. Use specialist breathable paints available from lime suppliers and others sources. Some types of harling are self-coloured and not painted. Paint removal methods. Always start with the least aggressive method
  2. Roger uses one of his favourite products for treating rising damp internally in brick walls.We show you how to treat damp walls in an old house internally wi..
  3. A cob pizza oven dome is a basic structure built out of a combination of mud, sand, water and straw. The dome is constructed over an oven hearth, which is created from cob, stone slabs, brick or fire bricks.Once the hearth or base has been developed, a builder may begin to construct the wood fired pizza oven dome. Domes constructed out of cob consist of clay, sand, soil, water, and straw to.
  4. Dub out any deep holes in the wall with a haired lime mortar, rebuilding defects with cob blocks, bricks or stone as appropriate. Treat wooden lintels with preservative and counter batten with oak lath if rendering over them. Apply a 3 mm harled coat of Secil Consolidation Mortar to provide a key to the wall
  5. Cob is a very old technique of building with earth and fibers which consist of stacking moistened earth balls reinforced with fibers to build a monolithic wall , , , . This technique has been used for thousands of years in all kind of climates and highly resistant to weathering, due its porous nature; and it can withstand longer duration in.

If you've never lived in a mobile home, there's one thing that we all hate - those darn strips on mobile home walls that they use to hide the cracks in the drywall. Mobile homes are made with pre-wallpapered dry wall, then matching strips are made to hide the gaps, because they're made as quickly and cheaply as possible However there are several major cracks in the cob walls throughout the building requiring extensive strengthening and repair to ensure a safe building for visitors. The trusts' goal is to form the best team to ensure the repairs are completed sympathetically, respecting the historical significance of the building

Cob Workshop - Building Cob Walls

Foundation Wall Crack Repair in Connecticut & Westchester County, NY. It's not that uncommon to find cracks in the foundation walls. However as minor as these cracks might seem these can turn out to be pretty dangerous as one small crack can lead to many severe foundation damages Insulating Lime Plaster Walls; Bag Rubbing; Lime Pointing; Plaster Lath Work; Painting Lime Plaster/Render; Work Examples; Useful Info. Cob & Lime - The Basics; Fixing cracks in Cob buildings; Avoiding Cob Deterioration; Cob Wall - Lime Layering System; Pointing with Lime Putty; Testimonials; Contact U Basement wall cracks open the door for insects and rodents. Nothing makes a basement more unappealing then bugs, spiders and cob webs. When a crack in your foundation wall gets wide enough you have opened your basement door to the great outdoors. Structural problems tied to a vertical foundation wall crack. The number one question most.

Painting Lime Plaster/Render - Cob & Lime Cornwall

Handyman Demonstrates Easy Way To Repair Crack In Wal

----- Original Message ----- From: Bob Smolen To: coblist at deatech.com Sent: Tuesday, September 16, 2008 8:21 AM Subject: [Cob] crack in plaster I have a small section of cob wall that I have covered with 2 layers of a coating of 3 parts sand , 1 part clay, and 1 part lime. I spread this on in a fairly dry mix and let dry for a week during a. Crack-sealing is an inexpensive preventative maintenance treatment that delays roadway deterioration. Crews grind open cracks and apply sealing material directly into cracks. Flexible, rubberized asphalt sealants bond to crack walls and move with the pavement, to prevent water from entering the road base

the walls are ~18 in thick and the guy said he was using a whacker to compact the dirt once in the form. Cob could be formed like this. A few have large cracks like an inch wide or more, perhaps from settling foundations, but the cracks are eroded enough to make you think they've been cracked and standing happily for centuries.. distributes shrinkage cracks throughout the wall, acting as reinforcement, preventing the formation of large fissures which are often the cause of premature structural shear failure. Construction methods Cob walls are traditionally built off a stone plinth or 'pinning', normally 300mm t

REPAIRING cracks in a COB wall (earthen plaster) - YouTub

The final ingredient you need for cob is fresh, long straw (not hay), but it must be dry - once damp its strengthening function is compromised. On top of strength, the straw helps absorb movement and spreads out stresses, creating numerous hairline cracks rather than single, large cracks that are likely to splinter a wall in two While cement and stucco coats do fail the primary cause is a failure in the coating (cracks) as opposed to vapor/moisture migrating through the wall. The coating failure usually has a lot of moisture in liquid form trapped between the cob/adobe surface and the exterior coating (usually cememt/stucco)

If vertical cracks develop, cob or clay tiles can be used to fix them before moisture penetration risks damaging the wall. Cob walls are traditionally left bare or rendered with lime to allow them to dry out naturally after becoming wet. Cob is fire-proof, resistant to seismic activity, and tends to be inexpensive, albeit time-consuming Miscellaneous Q & A about Cob Building. Michael G. Smith has a background in environmental engineering, ecology, and sustainable resource management. In 1993, along with Ianto Evans and Linda Smiley, he started the Cob Cottage Company, a research and teaching group focused on reviving and improving traditional forms of earthen construction Because cob building requires no forms, we can build our walls into any shape we choose. Curves, niches, arched windows and built-in furniture are common features in cob buildings. Cob building requires no cement, no expensive tools or materials and is a 'people friendly' way of building. Once the material is dry, cob is incredibly strong

Lime Plastering Using Natural Hydraulic Lime - Cob & Lime

Cob Repair Guide Sheet How to Repair Cob Building

Cob therefore lends itself to organic shapes: curved walls, arches and vaults. Building with cob is a sensory and aesthetic experience like sculpting with clay. You can add on, cut out, or reshape at any time, even after the cob is dry Straw bale building is done with straw bales (not hay bales), which then need to be covered - usually with earth plaster, lime plaster or cement stucco **. A covering is just that - a cover material (generally, layers totaling about 1″ or so thick) that protects the bales. Cob is a lot like earth plaster, although it is much more specific

Lime Rendering Using Natural Hydraulic Lime - Cob & LimeMasonry and foundations - Straw Clay Wood

A small cob oven should work, but might need smaller wood, closer tending, and longer burning. Q: Do you find that cleaning the oven causes damage? A: I'm pretty careful to keep the hard edges of my scuffle and peel away from the oven walls. It is harder, sometimes, to be so careful when tossing wood into a raging fire_but not impossible First step: find anything on hand to fill the gap between the logs. This is where things got really creative for the original log cabin builders. Remember, Lowes wasn't around the corner, so it was basically anything they had within carrying distance that they could stuff in the gaps: grass, straw, manure, corn cobs, mud, goat hair, underwear Much will depend on the size of the cracks and extent of delamination.You may need to make a richer mix to help it adhere to the wall better. For example: 2:1 sand to lime by volume. You will be able to do future lime washes without issue.; in fact, you'll likely need to do one over the whole wall to cover the patches Repairing cob depends on the size of the problem. Non-structural cracks can be repaired with cob bricks (or cut-down cob blocks), larger cracks or defects with cob blocks. Rebuilding and repairing cob structures with cob blocks offers advantages over masonry and aerated blocks in that they The true joy of clay plaster is its incredible softness, and the way light plays on the wall. Drywall cannot hold a candle to the incredible texture of a fine clay plaster finish. As the day goes by, and the light changes on the walls the color and textures shifts and subtly changes, too. It's wonderful Even slight cracks in the render of a building can allow water to penetrate and become trapped between the render and brickwork. This build-up of stagnant moisture will eventually soak into the brickwork/masonry and can lead to penetrating damp within the internal wall. This can create an unsightly and harmful damp problem in the property that will only deteriorate if not properly addressed