Showing posts with label Building Inspection Perth WA. Show all posts
Showing posts with label Building Inspection Perth WA. Show all posts

Monday, April 25, 2016

why concrete tiles for roof?

By: Peter Huber
Posted By:BHIS

Ok lets continue where we left of in the last article, on the fact and fiction about roof tiles.

Property Inspection Perth WA

If you are worried about the usage of concrete tiles when collecting rain water, well there is nothing to worry about as we are assured that the surface of the concrete tile is a suitable surface from which to gather water for drinking, and best results are achieved when an appropriate collection system is fitted.

Building Inspection Perth WA

If you are building near the coast you also need not worry, as the prolonged exposure of concrete tiles have a proven record of resistance to corrosive atmospheres.
Similarly in tropical conditions the added weight of a concrete roof helps to counteract wind uplift during storms making it less susceptible to damage than some other roofing materials.
Normally concrete tiles require very  little if any maintenance due to their exceptional durability, if some is required then only the affected tile will need to be replaced.

Professional Building Inspections Perth

Cleaning of the tiles is also not  a necessity but Lichen and moss can be removed by high pressure jet water sprays or by the application of a specific chemical formula sold for this purpose of removing the lichen and moss. In fact the formula for the magic potion is this:-  200 grams of copper sulphate, to 4.5 litres of water The average roof will need ten times this amount, the solution is broomed onto the offending areas and eradication will take place over the following couple of months and it should be left to work on its own as the moss and lichen will gradually disappear. On porous tiles the solution has a residual affect as it remains and inhibits any future or early re-growths.

Professional Home Inspections Perth

When using copper sulphate solutions be careful that metalwork such as guttering is protected to prevent corrosive  action. Gutters should be filled with water by blocking the downpipes as any solution running into the gutter will be extremely diluted and not affect the metal gutter.
By comparison concrete tiles are very affordable and generally cost less than metal or clay covering, on most profiles the fit is neat and even, but the coating that is applied to the tiles is still subject to weathering and will eventually wear off and needs re-painting.

Building Inspection services Perth

So myths like, Lichen and Moss will eat into your tiles and weathering of the original surface coating makes old tiles porous, is all a lot of old wife’s tales and scare tactics, invented by itinerant traders.

Every so often we would like to publish questions with answers that our readers may have on renovating or building, so please share your comments.

Monday, November 9, 2015

Overcoming damp problems in your house | Professional Home Inspections Perth

By:Peter Huber
posted by:

From time to time the CSIRO is asked to suggest remedies for dampness caused by rain penetrating solid masonry walls, below are some of their invaluable findings and suggestions which are worth passing on.
Single-leaf construction cannot be expected to be water-tight, especially if it is subjected to wind-driven rain. If the wall thickness is increased it should be more resistant to rain penetration, but poor workmanship in the form of unfilled joints and un-tooled face joints can result in walls that are prone to dampness despite their thickness and apparent solidity.

Often people seek a quick and easy “brush-on” treatment, preferably to be applied from the inside, but we consider the latter to be unrealistic and a false economy. External treatment aimed at preventing the masonry from becoming damp in the first place is a more sound approach. Some possibilities are described:



Silicone formulations brushed or sprayed onto porous surfaces make them water repellent, so that water then runs down treated walls instead of being absorbed. There is a risk in this, however, because fissures wider than hairline crack are not bridged by these materials. The increased amount of water running down the wall during a shower can result in more water penetrating the wall, via such fissures, than before the treatment. With this in mind walls should be examined carefully, and repaired if necessary, before silicone is applied. Silicones deteriorate in sunlight and periodic reapplication is required if the wall is to remain water repellent.


This is a useful treatment. Two coats should be applied on the wall after the necessary preparation. A minimum preparation would be to repair gaps and defects in the mortar joints, but in practice “bagging” of the whole wall is advisable. A mixture of 1:4 cement: plasterer’s sand is suggested for this, the wall being “wetted down” before starting.


If organic paints are to be used “bagging” is an essential preparation. As long as the paint film is intact the system will be effective, but once cracking starts water will be trapped behind the paint. This water will take a long time to evaporate and, under adverse conditions, the wall can become progressively damper. In any case the life of the paint system there-after is likely to be short.


This treatment is virtually permanent and should be effective in all but the most severe conditions. For resistance to rain penetration a rough-textured and porous rendering is normally more effective than a dense and impermeable plain finish. Suitable cement: l lime: sand mixes are given in the British Standard Code of Practice CP 221, “External rendered finishes”, available from the Standards Association of Australia.

The discussions and hint given above will suit most homes that have damp problems, in fact silicone treatment seems to be the most popular, especially in the case where the external walls are face bricks.

If you have any further questions please call our office.

We want you the reader to write to us on, any Building matters, and questions or if you seek advice, we will gladly answer any topic that you wish us to discuss, so please send your letters to “B. & H. I. S.” C/O. 17 Battye Road, Kardinya, W.A. 6163 or fax/ph (09) 331-3031

Monday, August 10, 2015

Building Inspections reports Perth | Improving Sub-Floor Ventilation

By: Peter Huber
Posted By:

Improving Sub-Floor Ventilation

We will look at improving sub-floor ventilation which if not done correctly can be a cause of decay to timber components.

The other day we were asked to inspect an older style home in Nedlands it was a grand old mansion with timber flooring through out, massive ceilings space and it was oozing with old world charm. Generally the home was in good shape some of the roof timber were showings signs of sag and ageing but one room in particular was extremely cold, and it almost reminded me of the spooky stories one reads about cold rooms in haunted homes, but no such luck.
It turned out, after removing the inspection (male/female) opening in between the floor joists, it was obvious why the room was so cold.

Building Inspections reports Perth:

For starters the distance between the ground and the floor was very close, the home was on a sloped block, and sub-floor ventilation was minimal. I will insert some data facts as supplied by CSIRO to us, on how to improve the subfloor ventilation with some interesting and commonsense applications, but you may well ask what has a sloping block to do with it, well when water via rain is deposited around the perimeter of a house if the home sits on a flat block of land the water will seep into the ground vertically down, if the block is sloped the water that may pond in areas can and will flow down the hill and seep into the ground as it progresses down the incline of the land and hence we get damp and moisture under areas that would mot normally get damp on a level block.

Now the CSIRO Division receives an steady stream of requests for advise on prevention and correction of decay in flooring and in the majority of cases the problem is one of inadequate subfloor ventilation, that is for a free flow of air under all parts of suspended timber floors.

In older buildings the problem can be complicated by an ineffective dam-proof course, by leakages from water supplies or wastes or by the discharge of storm water into the sub-floor cavity, further more in older buildings the provisions for under-floor ventilation is often inadequate.

Building Inspections reports Perth:

We shall take a case in point, where in a double brick dwelling circa(1920) most of the timber flooring had to be renewed. During the repairs the size and numbers of openings in the brickwork below floor level was increased because, with a few exceptions, the only provisions originally provided for ventilation was the openings in the brick work beneath the doorways. Before the new flooring was laid, extra openings were provided within one(1) to two(2) meters of every corner of every room and midway along any wall over five(5) meters long. Each of the new openings occupied the space of at least two bricks.

In addition because of the low sub-floor clearance and the difficulty of providing good cross ventilation, plastic sheeting was spread out over the ground and under all new flooring so as to reduce the area from which soil moisture could evaporate into the sub-floor cavity. Mortar droppings and other debris were removed from the inside of all external ventilator openings and finally the ventilators themselves were replaced.

Replacement of the ventilators was an essential part of the repairs. Surprisingly the smaller of the original terracotta vents provided for rather more free airway than the double brick size, even though the latter had one more opening. However in practice, nether allowed for much air exchange between the subfloor space and the outside because the openings had been blocked by spiders and assorted debris. The pressed metal vents that were used to replace the original terra-cotta air bricks allow for about ten(10) times as much air flow through each opening. This together with the other measures taken should ensure that conditions conducive to decay do not develop again under that floor.

Adequate subfloor ventilation is also an essential requirement which is often overlooked when remedying the problem of excessive dampness in walls, by effectively ventilating all subfloor cavities, moisture that evaporates from the soil or the foundation is removed and the sub-floor humidity is prevented from rising. However achieving an airflow across or along the sub-floor space can be difficult in some houses, especially in terraces where there can be problems in providing vents at both ends of the house.

Building Inspections reports Perth:

In case like that the Division often recommends the utilisation of disused fireplaces as a means of venting. If decorative facing is placed over the front of a fireplace openings cut through the hearth to the sub-floor space and a cowling or chimney pot placed on top of the chimney then a n up-draught will be created when the wind blows over the roof and air will be drawn from under the floor.

Any questions that our readers may have would be gladly welcomed and endeavoured to be answered as seen fit.