RESIDENTIAL
Design Services


" Watch out for us on HGTV's
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( Last updated July 18, 2007 )


Home | Removing a Bearing Wall ? | Underpinning & Benching ? | 
Do you need a Building Permit ? | Need an Engineer for a Building Permit Application? |
 | Need an Engineer to Inspect ? | Cracked Walls ? | Sloping Floors ? | Site Visit | 

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Removing a Bearing Wall:

You may want to remove a bearing wall...or at least, you think that it's a bearing wall. Don't assume that just because the wall studs seem a bit loose, or because the joists above the wall are continuous across the top of the wall, that the wall is not "load-bearing". We often find that older homes were constructed with continuous joists across the width of the house, yet the floor joist relies upon the extra support that it gets from the wall and supporting floor joists below. Remember, even if the floor above does not fall down after you remove a wall, you may be creating an over-spanned floor condition which is potentially unsafe !

We can usually determine whether or not a wall is load-bearing by making a site visit to inspect. Sometimes, we may need to cut a small hole in the ceiling so that we can confirm the size and direction of floor framing. In some circumstances, we can make conservative (safe) assumptions without cutting holes, however these assumptions need to be verified by the Contractor during construction.

Most jobs like this involve one site visit, and about 1 day of our work in the office to draw-up a partial plan and specify the necessary beams and posts. Design costs for these types of projects vary depending upon the number of beams required and the complexity involved in transferring loads from the end of new beams down to the foundations below. Building permit fees for simple interior renovations like this are quite inexpensive, sometimes less than $100.

Key Issues Are:

When you remove a bearing wall, a beam with support posts needs to be installed to replace the bearing wall. Electrical, Heating, and Plumbing services may be inside the wall, and these components need to be considered in the context of the renovation.

Beam may be "dropped" below the ceiling, or "flush" mounted, so that it is hidden. It is less expensive to supply and install a dropped beam. For a wood beam, the approximate depth of the beam will be equal to the span length divided by about 17. For a steel beam, the approximate depth of the beam will be equal to the span length divided by about 24. ( This is only a guideline that you can use for planning purposes and should not be relied upon to replace competent engineering design. )

Posts at the end of the new beam need to be supported properly. Typically, we look for support from a beam in the floor below, or we try to arrange for posts to be supported on masonry or concrete walls from below. Sometimes, considerable additional work is needed to provide the proper support for the new posts, and this work can add considerable cost to your project. Failure to provide proper support posts can lead to serious consequences, even collapse of the floor above.

We strongly advise you to have an engineer design your beam and posts, and to get a building permit prior to commencing construction.

Underpinning & Benching ?

If you are planning to lower your basement floor, then you will require a building permit, and almost undoubtedly, the Municipality will require that you retain a Structural Engineer to prepare drawings for you.

There are two common methods by which the basement floor of your home can be lowered:

1. Underpinning the foundation walls: In this method, a sequence of holes are dug-out from under the footing of your home. ( The footing is the concrete or brick pad which spreads the load of the foundation walls onto the soil. ) Typically, a series of 4' wide holes, separated by 8' of undisturbed soil, is prepared and filled with concrete. The top 2" of the concrete filled hole is packed with non-shrink grout, rather than filled to the top with concrete, so as to avoid the possibility that air pockets are present. Once the first series of holes are filled with concrete, the adjacent 4' wide segment is dug-out, and the underpinning process continues. Here, the idea is that you extend the footing of the house to a lower level, which then permits you to dig-out the soil from the inside of the basement, without undermining the foundation walls of the house. The process is very labour intensive, and quite costly.

2. Benching: In this method, a stable soil slope is maintained between the lowered basement floor level, and the underside of the original footings (to avoid undermining the footings). Then, a steel reinforced concrete "bench" is poured over top of the stable soil slope, to ensure that the soil slope is protected. This process is less expensive, however it leaves you with a concrete bench around the interior perimeter of the basement.

The municipality is also very likely going to ask you to have your engineer carry out periodic inspections of the underpinning operations, and to provide the municipality with Site Inspection Reports which confirm that the underpinning work is being carried out in accordance with the design.

Make sure that you check the level of the sanitary sewer connection before starting this type of work. If the sewer is higher than your basement floor, then you may have to install a sanitary ejector pump in the basement at an additional cost.

Make sure that underpinning of your foundation walls does not undermine your neighbors footings. This is quite possible if your home is very close to your neighbors house. If you accidentally undermine your neighbors footings, then you may need to underpin their footings as well to ensure the stability of your neighbors house.

Finally, make sure that the water table is not so high that your new basement floor is "underwater". You should also make sure that the water table is at least about 24" below the level of your new underpinned wall, since soil bearing capacities must be reduced when the water table is near the surface.

Do you need a building permit ? ( probably if you're checking this website ! )

If you are carrying out a construction project on your home, you probably need a building permit. Undoubtedly you will need a building permit if you are making an addition to you home, or if you are making any changes to walls or partitions. It is best to call your municipality to find out if you need a permit. For the City of Toronto, go to http://www.toronto.ca/building/building_permits.htm

Many people don't want to apply for a building permit because of the time and cost associated with the approval process. However, you may be surprised that many small renovations can be carried out under a Fast-Track permit, which can be obtained on the same day that you make the application.

We strongly recommend that you get a building permit for your renovation, for the following very good reasons:

1. It ensures that plans for the project have been clearly documented.

In order to build anything, it is best to prepare some kind of plans in advance of construction. By going through the motions of preparing drawings for the project, unforeseen problems can be avoided, and a clear picture of the overall scope of the project is defined. Most people need drawings to help define what it is that they want to achieve. By having clear construction documents, you can get true "apples-to-apples" prices from different Contractors for the same scope of work.

2. It helps to ensure that the project conforms to minimum standards

Before a municipality grants a building permit, they usually want to check over the plans for compliance with the Building Codes and Zoning by-laws. Sometimes, the municipality puts most of the code compliance onus onto the design professionals that prepared the plans for the project. This is no trivial matter, since very significant liability is attributed to design professionals and municipalities when a building permit is issued.

3. The municipality will "checkup" on your construction work as it progresses

As part of the building permit process, most municipalities will send inspectors out to check that work is proceeding in accordance with the approved permit plans. These inspections normally visit at key stages during construction, and the site inspections are intended to ensure that the construction work conforms to the approved permit plans. Regular inspections keep the Contractor's honest and on-their-toes, and serves as an independent check that work is being carried out properly.

4. It's the Law:

In most cases, you are required by law to obtain a building permit for your project prior to construction. If you renovate your house without a building permit, then you could be held liable to all future owners of the house for creating hidden defects in the building structure. Even worse, you could be required to tear-down your renovation in the event that your construction work does not comply with the building code or with zoning by-laws which may apply to your home.

It is best to check with your municipality to see if you need a building permit for your renovation, however if your project requires the removal of any walls or other elements which may be of a structural nature, it is likely that your municipality will require you to get a permit. Try calling your municipality and ask to speak to someone about requirements for building permits. Most municipalities are very helpful in this regard. ( Don't be afraid of the Building Department - they are there to help. )

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Do you need an Engineer for a Building Permit application:

You may be frustrated because your building permit application has been rejected and you have been told that you need an engineer to review and stamp your drawings. A municipality is entitled to demand that an engineer be retained to review and approve the construction documents when a project ( or a part thereof ) does not conform to all of the requirement and limitations of Part 9 of the Ontario Building Code.

Many house designers don't know exactly when they need an engineer, and more and more home designers are hiring engineers to specify the "structural" parts of their designs. By doing so, the designer is relieved of the structural engineering "liability", and the Owner can rest assured that the structural design is correct. Often, Designers and Architects ask the Owner to hire structural engineering services directly so that the designer is "out-of-the-loop" of liability for this part of the design.

Of course, Part 9 of the Ontario Building Code is the part which applies to Housing and Small Buildings, and this part of the Code is written so that individuals without explicit technical training in Architecture or Engineering can design and construct buildings without having to engage the services of an Architect or Engineering professional. Your drawings may have been prepared by an Architectural Technologist, an Interior Designer, or a Design-Build Contractor, all of which may be well qualified to design the structure of your home in accordance with Part 9 of the Ontario Building Code.

A building which complies with all parts of Part 9 does not need to be designed by either an architect or and engineer, and a municipal building department can issue building permits for this type of construction. It is only when parts of the project do not conform to the limitations of Part 9 that the municipality requires professional design by an architect or an engineer.

As of January 1, 2006, Ontario's new Bill 124 will come into effect, and this will mean that most building permit applications which are made to a municipality will need to be "stamped" by a "designer" who has passed certain building code examinations. The new requirements are an attempt to improve the quality of building permit submissions, and to place much more responsibility on the shoulders of individual building designers (who now will need to be insured). In return, the public can expect building permit waiting times to drop from an average of about 8 weeks, down to a legislated maximum waiting period of 10 days !

The application of Part 9 to buildings is generally limited to building which are 3 stories or less, and have a building area (footprint) not exceeding about 6460 square feet. However, even if your building conforms to the above restrictions, there are many other parts of the building which may not conform.

Common examples of construction which may not conform to Part 9 include:

Designs with large open areas - designs where clear spans of floor systems exceed approximately 20 feet or about 6.0 m commonly do not conform to Part 9 and require engineering to ensure sufficient strength, or to ensure that floors are sufficiently rigid and do not "bounce".

Designs which incorporate vendor engineers products, such as Engineered floor joists ( commonly called I-Joists ) and engineered wood beams ( commonly called LVL's, Microlam or PSL beams ).

Designs with basement foundation walls which are more than 8'-2" high cannot be designed with Part 9 and require engineering. It is currently popular to have 9' ceilings in residential basements, and these types of foundations cannot be designed with Part 9.

Designs which include few or no interior walls and also incorporate large window openings in the front, rear, or both. Homes such as this often require steel portal frames to be designed to carry lateral wind or seismic loads around window and door openings, even if they are "shielded" from wind by adjacent houses.

Designs where exterior walls exceed approximately 11' - 10" high without any lateral support. This condition commonly occurs in exterior walls, beside large stairway openings, where the stairway itself provides no lateral support for the exterior wall.

Designs which are to be constructed on soil which is incompetent ( typically where the soil bearing capacity is less than 75kPa or 1500 psf ) Many builders don't know when the soil is not sufficient to support the load of the house until such time that a building inspector arrives on site and stop's work. Unfortunately, many homes get constructed on poor soil, which leads to foundation settlement, cracked foundation walls, wet basements, etc.

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Need an Engineer to Inspect ?

You may have identified a crack in a foundation wall, or a sagging or uneven floor, and you are concerned that there may be a serious problem. We can make a site visit to try to evaluate the situation.

For Existing Homes:

Cracked foundation walls, cracked floor slabs, cracked exterior masonry, sagging floors, uneven stairs, etc.

For New Homes:

Poor soil conditions encountered during excavation, and the building inspector needs an engineer to certify that the soil bearing capacity is sufficient to carry the weight of the building.

As-built construction deviates from the approved permit plans and the inspector cannot certify that the as-built condition is acceptable.

The contractor makes a mistake and constructs part of the building in an incorrect or unconventional manner, and the as-built condition needs to be assessed by a professional engineer.

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Cracked Walls:

If you have a cracked wall in your house, you may be concerned that the crack is a symptom of a serious structural problem. You may be reassured to know that the vast majority of the cracks that we investigate are not serious in nature, and very rarely indicate that there is a serious problems with your home.

Cracks in Foundation Walls are very common. In fact, almost all concrete and masonry structures have some small vertical cracks which are usually of little consequence. Concrete foundation walls often develop some very narrow vertical cracks immediately after construction ( less than 1mm wide ), due to shrinkage of concrete shortly after pouring of the concrete. Long foundation walls of houses (walls longer than about 50') will almost always develop some minor shrinkage cracks after construction, especially if your foundation walls are constructed with plain concrete ( concrete which is not reinforced with steel reinforcing bars ). If water is entering your basement through a small vertical crack, you should take measures to seal the crack to eliminate the water. Harmful molds can develop in a damp basement environment which can be harmful to your health.

If the wall has cracked and the wall has shifted vertically across the crack, then the crack may be a settlement crack. Most settlement cracks are diagonal cracks, and can be an indication of poor foundation construction, or, poor soil conditions. Diagonal cracks can be a sign of a serious underlying condition. In some cases, the soil which is located below the foundations of your house can expand or contract slightly, causing cracks in foundation walls.

If your foundation wall has horizontal cracks, you should consult an engineer immediately since this type of crack could reflect a serious deficiency in the foundation wall.

Cracks in Above-Grade Walls in older homes is very common, especially those with plaster construction. Many older homes have undergone thousands of cycles of changes from humid summer conditions to dry winter conditions, which tend to cause underlying wood frame construction or wood lath to expand and contract, leading to deterioration of plaster finishes. Also, some older homes may not have been constructed properly, resulting in over-spanned floor joists and overspanned support beams. Many older homes were built before building standards existed, and before municipal building inspectors were around to ensure that homes were built properly.

When we need to attend a site, we charge a minimum fee for a site visit. Since residential projects are typically very small and total fees are not large, we cannot afford to offer free site consultations. Only in certain special circumstances do we waive our minimum site visit fee.

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Sloping Floors:

Sloping floors in any house are generally not a good sign. Sloping floors likely indicate one of the following conditions:

1. Settlement of the foundations of the house have caused parts of the foundations to sink, leading to sloping floors.

2. Improper floor framing: If the floor "sags" in some areas, it is likely that floor joists are overspanned, resulting in a sag in the floor system. If the floor system is also "bouncy", then this is likely the problem.

It is also possible that beams which support areas of the floor are insufficient, or that a bearing wall has been mistakenly removed during a prior renovation. A sagging floor could be due to inadequate structural support of an otherwise perfectly good floor system.

In some circumstances, sloping floors may indicate that part of the floor framing system has failed, however the floor has not collapsed due to some redundancy in the structural framing system. We often see second floor systems "sagging" around openings to 2nd floor stairways, where the stairway opening has been framed by simply doubling-up floor joists to form header and trimmer joists. Engineering analysis often reveals that trimmers need to be tripled or quadrupled, yet common practice is to simply use double-joists, which leads to skewed stairways and sagging floors over time.

Fixing a Sloping Floor:

Before spending considerable time and money trying to fix a sloping floor, you should consult a structural engineer to identify the cause of the problem. For example, if foundation settlement is the problem, then you may need to carry out remedial measures to prevent further settlement. Often people think that the settlement has " finished ", since the house is old. However, this is an incorrect assumption to make. Soils take hundreds of years to consolidate after they have been disturbed. While it is possible that future settlement will not be large, it is almost impossible to count-on. It would not be wise to invest thousands of dollars into a renovation, only later to find additional settlement cracks taking place. In our experience, where settlement has taken place, it is very likely that settlement will continue to take place for many years, unless some very direct and tangible measures are taken to curtail the settlement once and for all.

Once you have fixed the sloping floor, you may be able to correct the sloping floor surface by building-up a new subfloor over top of the existing sloping floor. 2"x4" sleepers which are "ripped" at an angle can be installed over top of the sloping floor joists, and a new subfloor installed on the the new surface.

Another way of fixing an uneven floor is to install a self-levelling cementitious grout, such as Maxxon's Gypcrete, and then, install a new subfloor on the new level surface. If you are considering this option, make sure that your existing floor system can safely support the increased loads.

Whenever floor leveling renovations are contemplated, you will need to maintain or modify the level of the top of the stairs, adjust the level of baseboards, window and door frames, install new finished floors, etc.

You should carefully consider the hidden liabilities which are contained within a home with sloping floors, since repairing a home with sloping floors can be very costly.

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Site Visit:

When we need to attend a site, one of our staff will come out and meet with you to discuss the matter at hand. Typically, we visit for no more than about 1 hour on site ( except when we need to take detailed measurements ). Our initial site visit is primarily a consultation to discuss structural engineering matters that affect the project. During our site visit, we may suggest ways to approach a problem or a situation, suggest possible methods by which a solution may be attained, etc. However, our initial site visit is a general consultation only, with no specific technical design recommendations to be given in our report.

Typically, our initial site visit includes a report which describes the structural situation, and recommends a general approach which may be suitable to solve the problem at hand. Our recommendations may be that we need to be retained to design certain remedial measures, or we may recommend that further investigation be carried out by us, or by another specialty consultant.

When we need to attend a site, we charge a minimum fee for a site visit. Since residential projects are typically very small and total fees are not large, we cannot afford to offer free site consultations. Only in certain special circumstances do we waive our minimum site visit fee.

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Our Fees:

The cost of having us provide structural engineering services for your project varies depending upon the complexity and size of your project. Residential projects are difficult to estimate without us first being able to review, in some detail, the amount of work which will be involved.

If you don't already have some plans drawn-up for the job, it is likely necessary for us to visit the house, and discuss the project with you. Since residential project fees are generally small, we cannot afford to provide you with free site consultations - we charge our site visit fee for this service.

However, if you have plans for the project which depict the scope-of-work, you or your designer can send us drawings, and we can give you a fee proposal based upon that scope of work. We do not charge for this type of proposal.

There are two approaches to delivering our services:

1. We "markup" design drawings provided to us with the required structural information, and then your designer incorporates this information into the design drawings. We stamp the final drawings for "structural content only" prior to your making your building permit submission.

2. We prepare separate structural drawings and specifications for your project. Here, we receive final CAD drawings of your project, and we prepare separate structural drawings. Our structural drawings are stamped prior to delivering you the final drawings.

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Delivery Time:

Since most of our projects are small, we rarely have a large backlog of projects. Typical turnaround time is about 3 weeks. In some circumstances, we can deliver projects faster.

Please feel free to contact us by e-mail or phone at 416 - 489 - 1228 x 221. For phone messages, it may take up to 48h for us to return you call. Please be patient, but feel free to nag us.

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