Construction Studies Portfolio

CONSTRUCTION STUDIES PROJECT

RAFT HOUSE NAME IVAN NICEVIC

EXAM NUMBER 106390

TEACHER PLUS

MR. MC MAHON

3

EXPERIMENTS

LEAVING CERTIFICATE 2014

CONTENTS 05 Acknowledgements

06 Introduction

09 General Information 10 Planing & Procedure

14 Research & Investigation

18 Building Elements

24 Making of the Model

32 Evaluation 33 What Have I Learned?

34 Experiments

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ACKNOWLEDGEMENTS I owe a great many thanks to a great many people who supported me during the making of my Construction Studies Project 2014, both model and design folio.

I take this opportunity to express my profound gratitude and deep regards to my Teacher, Mr. McMahon for his exemplary guidance, monitoring and constant encouragement throughout the production of my project. At many stages in the course of this research project I benefited from his advice. I would like to thank him for guiding and correcting various works and ideas of mine with attention and care. He was always available for all of us, and he was ready to help and support us throughout the production of our projects. I would also like to acknowledge the after school classes that my Teacher made available for us.

I would like to express my deep gratitude to all staff and the Principal of Saint Caimin’s Community School, who helped or supported me in anyway during the making of my project.

I would like to thank my amazing friend Brana Pantelic for providing me the photos of the raft house, several times, due to my inability to visit it at a particular time.

Last but not the least, a special word of thanks to, my grandparents, parents, sister and friends for their constant encouragement and help in ways unknown to them during the preparation and production of my Leaving Certificate Project, without which this assignment would not be possible.

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MAP OF BELGRADE CITY WITH SAVA & DANUBE RIVERS

INTRODUCTION Introducing chapter will include the quick description and explanation of what my project is.

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My project is a raft house. It is a wooden building floating on water. In Serbia, where it is also located, we call it “сплав” /splâːʋ/. Literally translated to English it means raft, but I would however translate it as a raft house. This raft house is located in Belgrade, the capital city of Serbia. It is floating on the river Sava, one of the two rivers in Belgrade, located 9 km far from my house in Belgrade, and about 15 km from the centre of the city (see page 6). The Belgrade Tourist Map at the top of this page shows the two rivers in Belgrade, the Sava and the Danube. My raft house is located about 6 kilometers south of the edge of the map. It was built in 1981, by my grandparents and my father.

Until now it has been floating in the same position and looks exactly the same, as it did 30 years ago, back in the last century.

There are many types of raft houses in Belgrade, differing by their purpose,

materials which they are built from, external & internal appearance, etc.

My raft house is used mainly for vacation and leasure purposes. My family, friends and I often spend sunny days enjoying the fresh air on the river, while the water gently rocks the raft house. People in Belgrade, also call those raft houses an escape to nature, from urban life in a city, yet they are so close to the city centre that even city bus lines cover those areas. It is something like a weekend house, except that I spend there every day during the summer holidays, not just the weekends.

Belgrade is well known for its raft houses. There are hundreds or possibly a few thousands raft houses in the city.

Private or public, but definitely most popular ones are the raft clubs, the big raft nightclubs floating on Belgrade’s rivers. Together, they attract thousands of young people, tourist and locals, every night in the week.

“The greatest pleasure of Belgrade, however, was its cafés and clubs. The Serbian capacity for night life is nothing short of amazing: some diehards go out seven nights a week, and still manage to make it to work the next morning.” - The New York Times After the success of those nightclubs, many restaurants and cafés have been built also on Belgrade rivers.

They provide an unique natural

peace and relaxation right in the centre of the city, but also an unforgettable experience for tourists from all over the world.

“The most recognizable nightlife feature of Belgrade is the floating river clubs or barges (called “splavs” or “splavovi”) that are spread along the banks of the Sava and Danube Rivers.”

- Belgradenet.com

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GENERAL

INFORMATION

W

hy Raft House?

I chose to make a model of my raft house because I think it is a very different and original idea compared to some other projects. I also have so many memories related to it, which means that it has emotional significance for me. After I was born in 1995, and when I left the hospital with my parents, the raft house was the first place they brought me because my grandparents were there, and there were no mobile phones at that time. From that moment they also called me a raftsman. It is a place where I learned to swim for the first time and where I had so much fun and memories of happy times with my family, cousins and friends.

My granddad has a small cardboard model of a raft house in Serbia, so since I moved to Ireland two years ago I decided to make my own bigger and more realistic model which will be to the scale of 1:10.

History Background: The raft house was built in 1981 by my granddad, my dad and the leader of the project, a man known as “Captain Dragan”. I never met him personally but from talking to my granddad I found out that he was well known man on Sava river. He had the title “Captain” because he had a ship and he was volunteering for the river police. Also he had a big raft house himself.

This is why my granddad went to him to seek for help.

Dragan was very experienced man in building these houses, and he used to say: “Building a raft house is a simple process if you know exactly what are you doing.”

Therefore, building a raft house took only about two months and when it was finished it was used by my grandparents, my dad and my aunt. Just like me, they have spent a lot of time in that raft house.

The idea was to build everything from the most natural materials as possible. My granddad didn’t want to ruin nature around the raft house. He decided to build everything from wood, except the foundation, where iron and metal were necessary. At that time in the 1980s you would only see a few raft houses in this area, where as today (satellite image on the page 8), they are tightly packed one after another because there are so many of them.

Main Design Elements: It consists of a raft and the house standing on it. The raft is also a foundation which is made of iron tubes and metal barrels. Barrels are empty and hermetically closed, they hold the weight of the raft house and this is what makes it float on the water. They are held in place by long iron tubes. On top of that goes two layers of wooden beams and then the floor and the actual house.

It has three sideways at the three sides of the house and a verandah in the front of the house.

When it was built in 1981 it used to have a boat sliding on a thick rope which was tied to the raft house and a small dock at the bank. This boat was used to travel from the riverside to the raft house. Many years after when my dad inherited the raft house he decided to build a bridge, for ease of crossing. I was also involved in building a bridge, few years ago.

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PLANNING

& PROCEDURE

RESEARCH DRAWING PLANS MARKING OUT MAKING & ASSEMBLY FINISHING

T

here are different stages which need to be accomplished in order to make this project. The first phase is research. I don’t need to do as much research as expected of someone who is making a model of a building, because I have worked on this raft house for years and I already know how it is built, the main measurements, etc.

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Research:

Drawing Plans:

Because the raft house is located in Serbia, I was unable the visit it at the time we started our project in October 2013. To get started I talked with my granddad about the main elements and their measurements.

Also, I asked my friend to visit it, take some photos and exact measurements which I needed in order to get started. My plan was to work with the information I got from my granddad and my friend until my next visit to the raft house in December for Christmas holidays.

Using a Google SketchUp, CAD software, I designed a 3D structure model to help me visualize the end product.

This way I made it easier for myself, to read the measurements and I saved time while making the structure of the raft house. Also, I didn’t want to make it too complicated, so I drew only what was necessary in order to make it cleaner and simpler.

The three main parts are colored in different colors, the base is white, the house is red while the roof is yellow.

Marking Out, Making Parts & Assembly: These processes were also made the same way I made a CAD model of a raft house. I divided it into three main parts, and made them completely separately, until the end when I glued them together. First I started with the foundation (base) part, then I made side walls separately and connected them with the frames for the front and rear walls, and at the end I made a roof.

Finishing: When the structure was made, there was still a lot of work to be done, but it was mostly repetitive work. I needed to cut the “Wooden Tongue Depressor� sticks and glue them to the frames I had already made. This way the walls will look very realistic and that is why I particularly like it.

The next step is to glue the roof to the house and the house to the foundation. This was one of the last thing I had to do, everythings after that was decoration and fixing.

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RESEARCH & INVESTIGATION

SITE VISIT, PHOTOS & DRAWINGS, MEASUREMENTS, NOTES, ETC...

U

nfortunately there are no architect’s drawing for the raft house, but regardless I will provide my drawings of it on the next few pages. The raft house was mainly designed

by Captain Dragan, which I mentioned before. He had a lot of experience in building raft houses which is the main reason why there are no official architect’s drawings. Obviously there were some drawings in the building phase, but those are not saved.

However, in December 2013, I managed to travel to Serbia for the Christmas holidays and to visit the raft house. As the winters in Serbia are very cold, the only thing that could help me improve the quality of the photos is the sunlight.

Luckily I managed to visit it on a very sunny day and take some photos which will be very useful for me during the production of my model and writing of this report. Not only the photos, but I took some important measurements that I needed in order to make a realistic and scale model. Measurements of windows & door, frames, wooden beams, verandah and roof height, diameter of barrels and pipes, bollard sizes etc. may seem

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unimportant, but they are actually very important in order to make a realistic scale model. Also I checked all the information that I got from my granddad and my friend, to make sure they are correct, and not leave anything to chance.

Panoramic 180 degree view of the river from the raft house.

This picture was taken during the winter of 2012. About 4-5 meters of water near the river bank was covered in ice. The bridge was surrounded by ice, which is an unusual event and might cause damage afterwards.

In the pictures on page 14, I was cleaning snow off the rafts with my friends.

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BUILDING ELEMENTS In this chapter I will describe and explain how the actual raft house was built. It will include detailed explanations of the construction techniques used, and also appropriate photos or sketches to support my explanations.

F

oundation:

The whole raft house has area of 36 square meters and its sides are 6 by 6 meters long.

It has a very unusual foundation, compared to normal buildings. Because it is floating on water, the foundation needs to have one key feature It needs to be able to hold enough weight and still float on the water.

Therefore it should be light, but strong.

This is why metal barrels are used in the foundation.

There are 30 barrels underneath the raft house, each with capacity of 200 liters. They are empty (filled with air) and closed hermetically, so that the water can’t get inside.

Because of this, they float on the water, and each barrel can hold up to 200kg. Because the weight of one barrel is 20kg, its bearing capacity reduces to 180kg which is it’s very maximum. Due to safety reasons, bearing capacity is again reduced, to 100-130kg per barrel. Which means that 30 metal barrels can hold up to 3.9 tons.

Because of the huge upward force exerted by the barrels, while they are pushed into the water by the weight of the raft house, they have to be fitted between iron tubes.

The wood is not hard and strong enough to hold them in place safely.

Moving on, there are fourteen iron tubes. Each 6 meters long, and 6 centimeters in diameter. Ten of those tubes are holding barrels in between each two, while other four are turned perpendicularly and they hold everything together and in place. The pipes are tightened together with a spe-

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Old tyres are used to prevent damage when a raft base is close to another raft or boat.

cial type of joint, commonly used for joining scaffolding pipes. It is of key importance that pipes are tightened well and safely, because if not, there is the danger that the raft house could sink.

If the raft house is located on a river like mine is, it is important that the

barrels are turned to be parallel with the flow of the river. Therefore the raft house will experience less force from the river flow, and it will be easier for it to stay in place. Which leads me to the next topic, anchoring.

View underneath the raft house, row between the barrels.

The image above shows two different types of pipe joint. A turning joint and a fixed 90 degree joint, from left to right respectively. They have different purposes, but are both used often.

A metal barrel is fitted between the iron tubes and then tied with a rope.

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Anchoring: Due to variations in the speed of the river flow and the fluctuations of the water level it need to be firmly anchored.

Firstly it has to stay in the same place all the time, regardless of water level and other conditions and secondly it needs to rise and fall respectively with the water level. These problems are solved by using two different components.

Two steel cables are set at, at least 45 degree angles in order to hold the raft house in the same spot. One end of a thick steel cable (20mm in diameter) is attached to the bollards on the raft house while the other end is tied at the river side, to any solid object or even a strong enough tree.

These cables prevent the raft house from moving away from the river side.

The second component are the iron tubes which disable the raft house to move against the river side and get grounded, therefore the raft house is secured in place. Those iron tubes are tied at one end to bollards at the raft house, while the other end is T-shaped and buried about 2 meters into the muddy soil. It is important that the back end is T-shaped, because the T-shape creates friction and therefore it can’t be pulled out from the soil. An interesting thing is that these tubes are usually buried when the water is at its lowest level.

Both of these components allow the raft house to move up and down with the water level, while still keeping it in the same place.

Floors: The raft house has two types of floors, the internal floor and the external floor. They are very similar to one another, but still have an important difference. On the iron tubes, which I described in the foundation, there are big wooden beams 10 by 10 centimeters that goes across, 6 of them in total. The next layer are smaller beams 8 by 6 centimeters that goes at 90 degrees to the beams underneath them. There are a few reasons why there are two layers of beams. Firstly because the actual floor of the raft house will be higher away from the water level. The second reason is a bit more complicated. The third layer is actually the timber floor which because of the weather conditions (snow, rain, sunlight, etc.) needs to be changed regularly every few years, depending on their condition. Therefore those wooden boards have to be nailed to the layer underneath. If they are to be nailed again and again to the 10 by 10 beams, they will be damaged very quickly. Instead, it is much easier to change smaller 6 by 8 beams when needed, roughly every 4 or 5 years, depending on their position.

For example, the pathway at the south side gets unsafe most quickly because of the high number of sunlight hours it gets every year.

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Walls: The raft house is a very small house, it has about 12 square meters of space inside, including a small kitchen and a toilet. So the only internal wall is for the toilet, but first let’s talk about the external wall because they are of greater importance.

The external walls are about 10 centimeters thick. They are built of timber frames with 8 centimeters glass wool insulation inside the frames. Frames are made of timber 8 by 6 centimeters wide. At the outside of the frames with insulation there is a nylon layer to make the wall waterproof, and then the wooden boards to cover it. They are painted with Sadolin, varnish for exterior wood to protect them from sun light, rain, and other weather conditions. On the inside, the frames are covered with 5 millimeter wooden boards, like those at the bottom of drawers.

While the inside wall is made only from 8 by 6 centimeter beams and then 5 millimeter wood board nailed to it.

Freshly painted new floor at the top and old floor at the bottom of the photo.

This photo was taken during the summer 2013, we were renovating the south facing wall.

Roof: The roof has a similar structure to the external walls. There are wooden beams 8 by 6 centimeters wide with insulation between them. Then on the outside goes timber of about 2 centimeters width. On top of that goes DPC, to make the roof waterproof and resistant to different weather conditions. All that is later covered with aluminum, in order to make it last permanently.

When the raft house was built in 1981 there was no aluminum at first, but only DPC with slates, after about 10 years, in the 1990s, my granddad renovated the roof and instead of new slates he made an aluminum cover.

My friend painting the new wall with Sadolin at the south side of the raft house.

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Windows and Doors: The raft house has three windows and one door. At the front side, facing the river, there is a big duble casement window and a door, while at the rear there are two small single casement windows, one for the kitchen and another for the toilet. All windows have external shutters which are locked from the inside for safety reasons. A door is made of two layers of wood and it has a regular lock.

Verandah: The verandah is at the front of the house, which gives it have a beautiful view of the river. This is where we spend most of the time. There is a small set-up table screwed into the wall, where my sister, cousins and I used to have meals as kids.

At the edge of the raft, there are two 10 by 10 centimeters wooden beams, which holds the roof above the verandah and the attic.

Those beams rest on the same 10 by 10 centimeters beams on the floor. The height of the verandah is only two meters because there is an attic above it, but the height of the inside of the house is as high as roof is.

Photo of the verandah at the left, and a joint between a vertical wooden beam and a roof above the verandah on the right.

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MAKING OF THE MODEL

B

ecause my granddad has a small cardboard model of a raft house, I always wanted to make my own model. When I first heard of the Construction Studies Project, I immediately knew it was a perfect opportunity to do such a thing. I decided to make a model bigger and more realistic than the one my granddad has. After thinking for a while, I thought that a scale of 1:10 would suit it best. It is just as big as I imagined it and it makes all measurements very easy to convert.

I still didn’t have all the information and measurements when I started making the model. At least, I had what I needed to start off. With help from my teacher, I made 6 wooden beams 10 x 10 x 600 mm, and 10 beams 6 x 8 x 600 mm along with few spare ones for the foundation of the raft house. After some experimenting I decided to use nails and glue to fit them together. Nails will hold them in place, while the glue will prevent them from spinning.

It took me a few classes to mark them out and put them together.

When I wanted to start going vertical and make the walls, I came across a problem. At the real raft house the

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wooden beams are nailed diagonally to the horizontal beam, but in the case of the model, it is almost impossible to do it the same way, on such a small scale. So, I had to improvise.

This is why I made completely different design in Google SketchUp and made it much easier and simpler for building a model. In the drawing above you can see the diagonal nailing of the wooden beams.

The design I made is not particularly good for the real raft house, but for the purposes of the model it is more than enough. This is because the model does not have a huge weight like the real raft house, so the improvised design will work in this case. You can see my design in the page to the right.

Finished model.

Improvised design of connecting the walls of the house to the foundation of the raft house. The problem occured because it was almost impossible to nail diagonaly on such a small model.

On the following pages I will show pictures throughout of the production of the model in the different phases, divided into steps. Step one will show testing the joints between the beams if the nails were used. Step two was to make and finish the foundation. Step three was to make the side walls while step four was putting them together. Step five shows the floor inside the house, while step six shows the whole house with front and rear walls. In step seven the rafters and roof structure were made. Step eight shows the ridge board joint. Step nine shows birdsmouth cut. While step ten is the finished structure.

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1.

3.

4.

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2.

5.

6.

7.

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8.

9.

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10.

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A

fter the structure of the model was finished there was still a large amount of work to be done. I used a bandsaw to cut the wooden sticks which looks very similar to timber planks on a smaller scale. You can see this process in the photo on the right.

Then, when they were cut to exact size, I glued them with super glue. I chose super glue because there is a lot of sticks that needs to be glued, and super glue works fine with wood, while it takes only few seconds to dry.

After gluing the sticks, there were a few more things left to be done. First I made an aluminum cover on the top of the roof, by using aluminum masking tape. This way it looks just the same as on the real raft house.

Also, I had to make three windows with the shutters and a door. The windows, more precisely shutters were very interesting part. I made them from the same wooden sticks I used for the walls and floor, except that I glued them at an angle so that they actually look like shutters. This also adds a realistic tone the model, which is my main goal.

These procedures took so much time and patience that I can hardly even explain, but the result was there at the end.

Cutting the wooden sticks.

Gluing the wooden sticks to the roof of the raft house.

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Putting aluminum masking tape on the roof.

There was only one part left to make. I left it to the end because I wasn’t sure if I’ll have enough time to make it. That part is explained under the title “Foundation” in “Building Elements” chapter.

Iron tubes that hold the barrels, which makes the raft house, actually prove its name. The question was, will I make it float or not?

There is an important part of Physics behind that question, so I did a bit of research. I learned how to calculate the bearing capacity of an empty barrel.

With that equation I calculated that scale model of a barrel can hold up to 110 grams (minus its own weight). Which means that 30 barrels can hold up to around 3 kilograms. I expected the raft house to be much more than 3 kilograms, but actually when i finished it, it worked out to be 2.5 kilograms.

Making the shutters for the front window.

After getting these measurements, hope returned to me that I could actually make it float. I contacted the company that sells the aluminum tubes, but they were very expensive, so I decided to make them from wood and then paint them silver. Thanks to my friend, who lent me a spray paint, it looked perfect at the end, and it was also much lighter than aluminum.

However, my big disappointment was that the weight of the foundation with 18 barrels worked out to be 600 grams, which is over the bearing capacity of the 30 barrels. Even though I already bought a kids swimming pool, unfortunately I was unable to make it float.

Measuring the weight of the raft house.

Weight of the foundation with 18 barrels worked out to be 618 grams.

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EVALUATION W

hen I finished the project, overall I was very happy how everything looked. The plan I made at the beginning of the project showed up to be very realistic as the raft house looks just like I imagined it 6 months ago.

However, it took me a lot more time than I expected.

Thanks to my teacher I was working on the project many hours after school, a few times even to 7 o’clock.

This mostly happened because of my bad evaluation. I expected to finish some parts in a much shorter time than I was able to, but fortunately I managed to finish it on time.

The model of the raft house looks very realistic, which I am very happy about. For example I didn’t want to make the walls and floors out of big boards, instead I used a lot of sticks, which gives an impression of a real building. The scale worked out to be perfect, all the measurements were easy to convert, and the model is just as big as I wanted. T he model gives a very nice glimpse of the real raft house. Everything is made of wood, which leaves the real impression of textures, smell, etc.

However the surroundings are still missing, the river and natural environment are the most important parts.

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On the other hand, I am very disappointed because I wasn’t able to make it float on the water. If I had more time for this project, I would focus on finding a way to make it float, and I am sure that I would manage it. Also the inside of the house is completely empty, and again, if I had more time this would be my second goal.

If I were to make it again, I would definitely consider making in float from the very beginning, and also I would make the interior of the house. Adding two beds, few closets, a small kitchen and a toilet sounds very doable. Also I would like to make a door that can actually open, or even a window that you can see through, and look at the inside of the house.

WHAT HAVE I LEARNED?

I

have learned a lot of different thing throughout the production of this project. Not only the skills that I gained and practiced, but also about myself.

However, I will start with skills.

1.

Skills

I have never worked this precisely with wood before. The raft house in Serbia was actually the only place where I ever did something with wood, and that was usually limited to cutting the boards and nailing them to the wooden beams. Therefore, modeling was a very nice experience and I really enjoyed it.

I used some machinery that I never used before, like a bandsaw, planer and also some hand tools like a chisel and marking gauge. I realized that there is a lot more that you can learn about wood and treating it.

3.

Myself

Throughout the making of the project I realized how much the raft house means to me, because I really enjoyed it and I was so excited when I was approaching the finish.

Usually I work when someone pushes me, but with this model it wasn’t like that. I learned that when I do what I like and enjoy, no one has to push me, I somehow manage to motivate myself, because I am looking forward to the end. This also motivated me to study more, so that I can get the points I need on the Leaving Certificate, and fortunately one day do what I love and enjoy doing. Also, I proved to myself once again that I am a very organized person, and that I can work alone as good as I work in a team.

Also I gained some experience in time management, because it’s my big issue. I can say that I improved a little, because I made mistakes with evaluating the time I would need to finish some parts of the project.

2.

Knowledge

I learned many different things, for example how to calculate the bearing capacity of an object made from different materials when it is submerged into the water. Also, I learned how the roofs are made, because I never actually knew that.

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1. EXPERIMENT To show the importance of DPC as a building material: Apparatus required: 4 bricks, a tray, water and a DPC

Method: 1. Set up the apparatus as shown in the photo.

2. Place two sets of bricks, one with DPC between and another one without, in a tray half filled with water.

Add some dye to the water.

3. Notice that water will start to creep up the brick, through capillary reaction.

4. The water will stop at DPC level on the brick that has DCP between it, but will continue to rise on the other set.

Result: DPC is seen to stop the rise of water in a structure, while without it, water continues on through capillary reaction.

Conclusion: DPC prevents water from creeping up along the walls of a building, and therefore is a must in every building to prevent dampness. DPC must be placed 150 mm above ground level in rising walls on both internal and external leaves.

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2. EXPERIMENT To prove the importance of a ceiling joist in the roof of a house: Apparatus required: A model of a timber roof frame, concrete block, and a results sheet

Method: 1. Set up the apparatus as shown in the photo.

2. Mark two straight lines on the results sheet at the external end of wall plates at the both sides.

3. Put a concrete block or any other heavy object and balance it on the ridge board.

4. Mark two new straight lines on the results sheet at the external end of wall plates at the both sides.

Result: When the weight was added on the ridge board, whole roof model structure spread and distance between wall plates was bigger.

Conclusion: Ceiling joist prevent roof to spread under some weight or pressure. If there were no ceiling joists, roof will spread, wall plates will move and possibly walls will collapse. The lower the ceiling joist is, the more stable and strong the roof will be.

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3. EXPERIMENT To show that the material is stronger at the edge than at the flat side: Apparatus required: Two stable support points, piece of material (timber) a concrete block and a meter stick.

Method: 1. Set up the apparatus as shown in the photo.

2. Measure the distance from the floor to the centre of the piece of material examined.

3. Add a concrete block to it and measure the new distance from floor to the deflected piece of material.

4. Repeat steps (2) and (3) when the material is turned to the flat side.

Result: When the piece of timber was turned to the flat side, deflection when the weight was added to it, was much bigger that the deflection when the piece of timber was turned to the edge side.

Conclusion: Materials are much stronger on the edge side than on the flat side, this is particularly useful in building timber roof structures and floors. Ceiling joist should always be turned to the edge side.

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CONSTRUCTION STUDIES PROJEC T 2014

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