Extensions...Advice and Ideas From A Structural Engineer

A successful extension can greatly improve a property in many ways. However there are risks to be addressed in the process. Structural engineer, Michael Hogan of Hogan & Associates has over 25 years experience in home and commercial building projects. We ask him to give us some advice and also some ideas. Learn about extending upstairs, and also about getting that perfect, "beam free" extension...
Structural Engineer, Extensions

About Our Experts - Hogan & Associates, Chartered Engineers

Hogan & Associates, directed by Michael Hogan have over 25 years experience in home and commercial building projects. Our services include consultancy, design, fault diagnosis, project management, surveys and compliance issues.

First of all, are there any dangers in building an extension? And, what are they?

First things first, the structural design must be right. That's vital for both comfort, and safety. The main items be considered from a structural angle are:

  • Tying in to existing structure. Exactly, how is this going to be done? Does the existing structure have any issues that could complicate this such as subsidence, cracking or poor construction.
  • Next thing to consider is the foundations and drainage. Many older houses in Dublin don't actually have foundations. They are built on a "wide wall" which may be undermined by adding an extension. Older houses also often have inadequate drainage systems which will need to be replaced or upgraded.
  • Finally, we look at loadbearing walls in the original house, and the impact the extension will have on the house structure.

After structure, the next thing I would consider is the comfort of the extended house. Comfort and liveability are an absolute priority. For example, a badly designed extension can make the original building darker. So position, and size of windows in the extension need to be carefully considered.

Could the extension have any other impact on the original house?

Absolutely, the next thing to consider is the various mechanical and electrical systems within the house. Will they be able to support the new extension. For example, it's important to review the following:

  • Is the heating system capable of handling additional load, or will it be overloaded? Older systems may have low level water leaks in pipes or at radiator valves. When new heating equipment is added, and the system is repressurised, these leaks may cause trouble.
  • Will there be adequate hot water? This is particularly important when new power showers, appliances or bathrooms or being installed.
  • Will the water pressure be adequate?
  • Are the existing heating controls sophisticated enough?
  • Is the wiring capable of handling additional loads? New extension will mean additional sockets, lighting, applicances. Particularly, in older house, the existing electrical infrastructure may need to be upgraded.

What about the actual construction. What are the potential pitfalls here?

Like design, the construction also needs careful planning to prevents problems "slipping in". The types of problems that can occur include poor workmanship, unsuitable materials, inexperienced personnel, lack of awareness of current regulations and standards, health and safety shortcomings.

On a positive note, all of these problems are preventable with proper planning. For example, a professional project specification will include exact details of materials to be used. And as part of our tendering process, we check that health and safety procedures are in place, and personnel are trained in those procedures.

What else can be done to reduce the risk of problems?

Of all areas, probably the one that has the potential to create the most stress during the project is contract administration. Who is controlling costs? Who is liable for defects? Who is liable for costs in scheduling overruns?

Again, the key here is in the initial planning. For example, a careful contractor selection process will identify a contractor with the experience and track record for your extension. Likewise, a well thought out contract will ensure all main eventualities are planned for. These include:

  • Terms & conditions of contract
  • Tendering/contractor selection process
  • Programming
  • Budgeting
  • Cost control
  • Value for money
  • Defects liability

What else can be achieved through good, early planning?

Virtually all heat loss is through structure - floors, walls, roof, windows or doors. All of these can be designed for best energy performance whether with retrofit or more effectively when new elements are being added. With proper planning, very good BER ratings can be achieved - even close to Passive House standards if required. Adequate underfloor insulation, external wall insulation, 'warm roof', thermal bridging treatment, airtightness - these are all aspects that have to be addressed at the earliest stages of the structural design - for new build and retrofit.

Is there any other key areas where advice would be needed

Yes, compliance issues need to be understood. Again, if they are addressed correctly, you can expect no future problems. However, the following issues may need to be considered:

  • Planning limitations
  • Building Regulation requirements
  • Conservation considerations
  • Exempt developments

Many homeowners already have a single floor extension, but would love to extend up stairs too. What's your advice?

Usually the most obvious and cost effective approach to extending a property is to do so at ground level. However extending over an existing single storey area can often be more useful and practical - in particular to provide additional or enlarged bedroom areas or bath/shower rooms.

A prerequisite for such a development is a careful assessment of the structure of the existing and its capacity to carry additional loading. A structural engineer is absolutely necessary for this assessment.

Most homeowners now want single"open plan" room between extension and original kitchen, without any beams where the old and new rooms meet. Is it possible to achieve a single clean, "beam free" room?

Very often downward protruding beams appear or remain after building work. These can be unsightly and tend to divide rooms and break up a potentially clear ceiling area.

It is usually possible to locate such beams above or integrate into floor or ceiling units. However, forward planning and careful structural design are needed to do so. Also the opportunity to do so cost effectively can pass if not considered early enough, preferably before any building work starts.

Great improvements can also be achieved for existing situations. With proper analysis and design, it's possible to perform a type of "keyhole" surgery, inserting a new hidden supporting beam, and removing the protruding beam. Very often these improvements can be designed and arranged to cause the minimum of disturbance and disruption to walls and ceilings. We've currently carrying out two projects where this type of "surgical" approach is being used to create a seamless extension, without a major disruption to the existing ceiling.

Contributors

Hogan And Associates, Olive Mount House, Olive Mount Road Windy Arbour, Dublin 14

Chartered engineering firm, Hogan and Associates provide a wide range of consultancy, design and project management services. We are directed by Michael Hogan, BE, MIE, MBA, C. Eng., FIEI, Hogan and Associates who has over 25 years experience in home and commercial building projects.
I wanted somebody with an engineering background because we were taking out walls and a lot of structural steel was needed...
Yvonne O'Driscoll from Mount Merrion, Co. Dublin
See Our Full Portfolio

Home and Garden Advice From The Experts

Paving For Driveways, Paths, Patios and Carparks

pickapro

As every estate agent will tell you, your front driveway sets the tone to your house. It might also dictate whether you can park comfortably outside your house - or whether you squeeze out the door and then step right into a nice puddle or mucky bit of grass! If you've been thinking about tackling it, well read on. We've asked our professional pavers on pickapro.ie for some inside knowledge on driveways and patios. As every estate agent will tell you, your front driveway sets the tone to your house. It might also dictate whether you can park comfortably outside your house - or whether you ...

Furniture Makeover With The Upholstery Experts

pickapro

Lumpy couches, wobbly chairs, scratched leather and dated colour schemes - it's all in a day's work for the team at Portmarnock Furnishings Ltd. We've presented our experts with 6 furniture issues to tackle. Read how your furniture can get a whole new wow factor, often for a fraction of the cost of replacing with new.

Lumpy couches, wobbly chairs, scratched leather and dated colour schemes - it's all in a day's work for the team at Portmarnock Furnishings Ltd. We've presented our experts with ...

Extensions...Advice and Ideas From A Structural Engineer

pickapro

A successful extension can greatly improve a property in many ways. However there are risks to be addressed in the process. Structural engineer, Michael Hogan of Hogan & Associates has over 25 years experience in home and commercial building projects. We ask him to give us some advice and also some ideas. Learn about extending upstairs, and also about getting that perfect, "beam free" extension... A successful extension can greatly improve a property in many ways. However there are risks to be addressed in the process. Structural engineer, Michael Hogan of Hogan & Associates ...

Bathroom, Shower and Wetroom Leaks - Advice from an Expert

pickapro

I've talked to Darren Kearns from Tilecraft, a Dublin specialist in bathroom renovations and leak repair about the topic of leaks. He explains why your bathroom and shower may be leaking and what your best course of action should be.

I've talked to Darren Kearns from Tilecraft, a Dublin specialist in bathroom renovations and leak repair about the topic of leaks. He explains why your bathroom and shower ...

Bathroom Renovations - Ideas from the Experts

pickapro

pickapro have talked to Rachael and Shane from Tile Rooms, bathroom and tiling specialists with showrooms in Newlands Retail Centre, Dublin 22. They gave us lots of interesting ideas but no rules! Their approach is firmly that it's all about getting what's right for you.

pickapro have talked to Rachael and Shane from Tile Rooms, bathroom and tiling specialists with showrooms in Newlands Retail Centre, Dublin 22. They gave us lots of interesting ...

Choosing The Right Contractor

pickapro

Choosing the right contractor is the most important factor in determining the success or failure of your home or garden improvement project. At Pickapro.ie we've interviewed hundreds of Dubliners about their experience in choosing a home improvement professional. Here are some of the tips that we've picked up from homeowners who have made a successful match. Choosing the right contractor is the most important factor in determining the success or failure of your home or garden improvement project. At Pickapro.ie we've interviewed hundreds ...

Building An Extension In Ireland

pickapro

They say space is the final frontier. Well, it is for many Irish homeowners anyway. For many of us, the solution lies in extending what we have. So, we've asked experienced Dublin builders from pickapro.ie to give us the scoop on planning and building a house extension. They say space is the final frontier. Well, it is for many Irish homeowners anyway. For many of us, the solution lies in extending what we have. So, we've asked experienced Dublin ...

10 Great Interior Design Tips

pickapro

Decorating a room or home can be an expensive business! Small wonder that so many of us play it safe with neutral colours. Perfectly fine, but maybe not exactly what we wanted. So, we've summoned the help of an experienced Dublin interior designer to give us a little courage for the trip. Decorating a room or home can be an expensive business! Small wonder that so many of us play it safe with neutral colours. Perfectly fine, but maybe not exactly what we wanted. ...

Timber Flooring Essentials

pickapro

A wooden floor must be one of the best home improvements any home owner can make. Yes, it adds immensely to the value of the house, but that's not the biggest benefit. They just look and feel so good. A timber floor is always stylish, and with a couple of rugs over it, is also incredibly cosy. Because of the range of colours in wood from purple to red to browns, timber will match just about every colour scheme. It's easy to clean, doesn't collect dust, and will probably outlast you. A wooden floor must be one of the best home improvements any home owner can make. Yes, it adds immensely to the value of the house, but that's not the biggest benefit. They just ...

Building A Sunroom Or Conservatory

pickapro

We don't get too many sunny days in Ireland, so it goes without saying that you don't want to miss the sun when it does shine. We have asked our experts for some advice on adding a sunroom or conservatory to your house. We don't get too many sunny days in Ireland, so it goes without saying that you don't want to miss the sun when it does shine. We have asked our experts for some advice on adding ...

Attic Conversions

pickapro

If you'd like some additional space, attic conversions are a great option. The beauty of attic conversions is that you are converting "dead space" without any impact on your garden or the rest of your house and at a lower cost than an extension. If you'd like some additional space, attic conversions are a great option. The beauty of attic conversions is that you are converting "dead space" without any impact on your garden ...

Preparing Your Garden For Winter

pickapro

Some people believe that when the weather starts getting colder and the fallen leafs have been raked up, it's time to put away the gardening tools and wait until next spring to work on their garden again. Wrong! Winter may seem like the end of the road for awhile, but there are a few things left to do to protect your garden during the harsh months ahead and prepare it for the following spring. So before you go inside and shut the door on your garden for the season,make sure you or an experienced landscaping company puts your garden to bed. A little preparation can make a huge difference to your garden in the spring. Some people believe that when the weather starts getting colder and the fallen leafs have been raked up, it's time to put away the gardening tools and wait until next spring to ...

Smart Tiling Tips

pickapro

If you're thinking about tiles for a new house or simply giving the old tiles in your house the occasional evil eye, then you're at the right place. We've asked our expert tilers to give us their tips. If you're thinking about tiles for a new house or simply giving the old tiles in your house the occasional evil eye, then you're at the right place. We've asked our expert tilers ...

Dog Friendly Garden Ideas for Dogs That Dig

pickapro

Geraldine contacted us with her problem - her dog and her garden are at odds. She tried to go for a low maintenance garden, but the dog keeps pulling up the black weed cover. She would also like to do something about an old concrete dog run on the side of the garden which is looking "a little worse for wear" Geraldine contacted us with her problem - her dog and her garden are at odds. She tried to go for a low maintenance garden, but the dog keeps pulling up the black weed cover. She ...

The Things Which Are Surprisingly Bad For Your House and Garden

pickapro

I wanted to find out what gets our home and garden professionals shaking their heads. I put it to them and got back a fantastically diverse set of answers. From structural engineers, to interior designers to landscapers, a lot of them had their say. I have to say, I'm guilty of at least one of these things myself... I wanted to find out what gets our home and garden professionals shaking their heads. I put it to them and got back a fantastically diverse set of answers. From structural engineers, ...

Sell Your House For More

pickapro

Decorating your house to sell is a completely different proposition from interior design for living. We've asked the professionals to tell us how to turn your property into a "must have" for buyers without breaking the bank. Decorating your house to sell is a completely different proposition from interior design for living. We've asked the professionals to tell us how to turn your property into a "must ...

Great Gardens For Children and Adults

pickapro

Do houses actually shrink over the Winter or does it just feel that way? There is of course a fantastic relief valve, more commonly known as the garden but it's often neglected at this time of the year. Like adults, children aren't enticed by a muddy strip of lawn and some drippy brown trees. So we've asked experienced Dublin landscapers from pickapro.ie to give us some inspiration for a garden that will appeal to both children and adults year round. Do houses actually shrink over the Winter or does it just feel that way? There is of course a fantastic relief valve, more commonly known as the garden but it's often neglected ...

Decks For Irish Gardens

pickapro

There's something intrinsically enjoyable about sitting on a wooden deck. It's back to nature - like a tree house for adults! www.pickapro.ie, the website of home and garden professionals have asked the professionals for advice on building the perfect deck. There's something intrinsically enjoyable about sitting on a wooden deck. It's back to nature - like a tree house for adults! www.pickapro.ie, the website of home and garden professionals ...

Ground Cover Basics

pickapro

When it comes to gardens, an important element of the foundation, is what's literally underneath your feet - ground cover including soil, grass, bark, chippings and stone. We've asked landscaping supplies specialists to give us practical advice on buying these very important basics. When it comes to gardens, an important element of the foundation, is what's literally underneath your feet - ground cover including soil, grass, bark, chippings and stone. We've ...

Plumbers Tips For Energy Efficiency

pickapro

There's a lot of us living with the joys and challenges of old fashioned plumbing. It's probably functional but it certainly isn't efficient. With fuel and oil costing plenty and new grants now available from Sustainable Energy Ireland to upgrade the efficiency of your home, it's worth looking at what can be done to upgrade the heating system in an older house. We asked several experienced plumbers what plumbing upgrades will give the best bang for your buck. There's a lot of us living with the joys and challenges of old fashioned plumbing. It's probably functional but it certainly isn't efficient. With fuel and oil costing plenty and ...

Roof Maintenance

pickapro

One of the most common, costly and often times ignored household maintenance projects is the roof over your head. Unless you've had water dripping on your head, it's easy to put it on the back burner until it comes up and really take a bite out of you and your bank balance. Read our quick guide to preventative maintenance for roofs to find out what you need to protect your roof and house. One of the most common, costly and often times ignored household maintenance projects is the roof over your head. Unless you've had water dripping on your head, it's easy to put ...

Condensing Boilers Cut The Cost!

pickapro

Replacing a 15 year boiler with a new high efficiency condensing boiler could represent a fuel saving of more than 25%. So if you annual oil fills typically cost €1,000, you're looking at a saving of €250 per year. Remember that there's SEI grants too. Interesting? Find out more from our boiler experts... Replacing a 15 year boiler with a new high efficiency condensing boiler could represent a fuel saving of more than 25%. So if you annual oil fills typically cost €1,000, you're ...

Garden Design Ideas

pickapro

With the garden being the top priority for 2007 according to our survey, we talked to landscaper Dermot Strong about tips for homeowners planning to improve their garden this year. With the garden being the top priority for 2007 according to our survey, we talked to landscaper Dermot Strong about tips for homeowners planning to improve their garden ...

Soundproofing Your Home

pickapro

With more and more Irish people living in high density apartments and houses, many of us are be feeling the pain of thin party walls. The long term solution may be higher standards in building but that won't help us now. Find out more sound proofing and how it can drastically improve your quality of life. With more and more Irish people living in high density apartments and houses, many of us are be feeling the pain of thin party walls. The long term solution may be higher standards ...

Sustainable Designs Reduces Running Costs

pickapro

How can you use sustainable design in your home to reduce energy costs Architect, Simon Hoe RIBA explains how. How can you use sustainable design in your home to reduce energy costs Architect, Simon Hoe RIBA explains how.

Awake To Bird Song In Your Garden

pickapro

Most of us don't know our blue tits from our chaffinches, but we still stop to watch the antics of our local friendly wildlife. They add colour and endless fascination to our gardens. pickapro.ie finds out how to entice birds into our gardens. Most of us don't know our blue tits from our chaffinches, but we still stop to watch the antics of our local friendly wildlife. They add colour and endless fascination to our gardens. ...

How To Choose An Architect

pickapro

Dublin architect Simon Hoe talk about working with an architect. How to choose an architect? How much will it cost and when are the fees paid? What information should the client bring to the design process? What happens next? Dublin architect Simon Hoe talk about working with an architect. How to choose an architect? How much will it cost and when are the fees paid? What information should the client ...

Choosing An Interior Designer

pickapro

How to choose an interior designer? What are the benefits? How much will it cost? And much more.. How to choose an interior designer? What are the benefits? How much will it cost? And much more..

How To Choose A Tiler

pickapro

We've asked Dublin tilers Karl Ronan Tiling to give us the benefit of their tiling experience. First of all - choosing a tiler. What are the most important questions to ask him or her? We've asked Dublin tilers Karl Ronan Tiling to give us the benefit of their tiling experience. First of all - choosing a tiler. What are the most important questions to ask ...

How To Choose A Landscaper

pickapro

Dublin landscapers give us the benefit of their landscaping experience. How to choose a landscaper? Is there a best time of year to hire a landscaping company in Dublin? What's popular in Dublin gardens now? And there's the all important top landscaping tips. Dublin landscapers give us the benefit of their landscaping experience. How to choose a landscaper? Is there a best time of year to hire a landscaping company in Dublin? What's ...

How To Choose A Garden Designer

pickapro

We've asked our pickapro garden designers to talk to us about garden design. First of all, why is a design useful? Next - how to choose a garden designer. What are the right questions to ask a prospective designer? How much do garden designs cost? What questions will the designer ask? What information should the homeowner provide? What happens after the design process? What are their personal design likes and dislikes And finally, their top garden design tips

We've asked our pickapro garden designers to talk to us about garden design. First of all, why is a design useful? Next - how to choose a garden designer. What are the right questions ...

Garden Maintenance Tips

pickapro

We've asked pickapro gardeners to talk to us about garden maintenance. First of all - how to choose a gardener. What are the right questions to ask? Next, how often should a gardener visit? Have they any tips to make garden maintenance easier. And how should we plan the garden in the first place to make maintenance easier in the long run. We've asked pickapro gardeners to talk to us about garden maintenance. First of all - how to choose a gardener. What are the right questions to ask? Next, how often should a gardener ...

Low Energy Extension Design

pickapro

Architect Simon Hoe outlines the stages through which a low energy, sustainable house extension is designed from the initial meeting to planning application. Architect Simon Hoe outlines the stages through which a low energy, sustainable house extension is designed from the initial meeting to planning application.

Windows - How To Choose

pickapro

It's hard to think of any other single aspect of your house that has to work harder than your windows. Windows provide security, insulation, light, ventilation, shield you from wind and rain, and allow you to enter and exit in an emergency Practicalities aside, they give your house character and make that all important first impression. It's hard to think of any other single aspect of your house that has to work harder than your windows. Windows provide security, insulation, light, ventilation, shield you from ...

Perk Up Your Garden For Spring

pickapro

It's official - Spring is here. How do I know? I've just driven past my local DIY store and seen racks of tempting boxes packed with bright little Spring flowers. Those little yellow and pink primroses and pansies - don't they just say (or squeak!) Spring. If you want to start enjoying your garden nice and early this year, these bedding plants are as good a place to start as any. But we've also asked our expert gardeners what else we can do to get the garden off to a quick start this year. It's official - Spring is here. How do I know? I've just driven past my local DIY store and seen racks of tempting boxes packed with bright little Spring flowers. Those little ...

Made To Measure Curtains

pickapro

Few home decorating decisions can cause as much soul searching as curtains and blinds! It's a long term investment which can make or break your room. We ask the experts for advice on choosing the right curtains and blinds. Few home decorating decisions can cause as much soul searching as curtains and blinds! It's a long term investment which can make or break your room. We ask the experts for advice ...

Find a Specialist

More Articles Like This

How To Choose An Architect

pickapro

Dublin architect Simon Hoe talk about working with an architect. How to choose an architect? How much will it cost and when are the fees paid? What information should the client bring to the design process? What happens next? Dublin architect Simon Hoe talk about working with an architect. How to choose an architect? How much will it cost and when are the fees paid? What information should the client ...

Low Energy Extension Design

pickapro

Architect Simon Hoe outlines the stages through which a low energy, sustainable house extension is designed from the initial meeting to planning application. Architect Simon Hoe outlines the stages through which a low energy, sustainable house extension is designed from the initial meeting to planning application.

Choosing The Right Contractor

pickapro

Choosing the right contractor is the most important factor in determining the success or failure of your home or garden improvement project. At Pickapro.ie we've interviewed hundreds of Dubliners about their experience in choosing a home improvement professional. Here are some of the tips that we've picked up from homeowners who have made a successful match. Choosing the right contractor is the most important factor in determining the success or failure of your home or garden improvement project. At Pickapro.ie we've interviewed hundreds ...

Building An Extension In Ireland

pickapro

They say space is the final frontier. Well, it is for many Irish homeowners anyway. For many of us, the solution lies in extending what we have. So, we've asked experienced Dublin builders from pickapro.ie to give us the scoop on planning and building a house extension. They say space is the final frontier. Well, it is for many Irish homeowners anyway. For many of us, the solution lies in extending what we have. So, we've asked experienced Dublin ...

Building A Sunroom Or Conservatory

pickapro

We don't get too many sunny days in Ireland, so it goes without saying that you don't want to miss the sun when it does shine. We have asked our experts for some advice on adding a sunroom or conservatory to your house. We don't get too many sunny days in Ireland, so it goes without saying that you don't want to miss the sun when it does shine. We have asked our experts for some advice on adding ...

Sustainable Designs Reduces Running Costs

pickapro

How can you use sustainable design in your home to reduce energy costs Architect, Simon Hoe RIBA explains how. How can you use sustainable design in your home to reduce energy costs Architect, Simon Hoe RIBA explains how.

Attic Conversions

pickapro

If you'd like some additional space, attic conversions are a great option. The beauty of attic conversions is that you are converting "dead space" without any impact on your garden or the rest of your house and at a lower cost than an extension. If you'd like some additional space, attic conversions are a great option. The beauty of attic conversions is that you are converting "dead space" without any impact on your garden ...

Inspiring Photo Ideas

House Extension Ideas From Dublin Architects and Builders

pickapro

Rear extensions, front extensions and sunroom extensions. We haven't forgotten the more unusual extensions too such as double height extensions, wrap around extensions or upstairs extensions. Rear extensions, front extensions and sunroom extensions. We haven't forgotten the more unusual extensions too such as double height extensions, wrap around extensions or upstairs ...