Types of surfaces in the home – Home Cleaning and Arrangement (Senior 3 Home Science) | Ganzaa

Home Cleaning and Arrangement

Lessons

Senior 3 · Home Science

Home Cleaning and Arrangement

4 lessons

Lesson 1 of 4

Types of surfaces in the home

22 min

Let's begin

Mutesi wipes three things in her family's house in Huye with the same wet, soapy cloth: the varnished dining table, the cement floor of the sitting room and the sisal mat by the door. The floor comes up clean. The table is left with a pale, cloudy ring where water crept under the varnish, and a week later the mat smells of mould because its fibres never dried. One cloth, one method, three different results.

The lesson is simple: a cleaning method must fit the surface. Before you can clean or arrange a home well, you must be able to look at any surface and say what it is made of, whether it is hard or soft, and whether water soaks into it.

Definition

Surface: the outside layer of an object that can be seen and touched, such as a floor, a wall, a worktop or a curtain.

Hard surface: a firm surface that does not bend or yield when pressed, for example tiles, glass, cement, metal and wood. Soft surface: a surface made of fibres or padding that yields when pressed, for example a carpet, a woven mat, a sofa cover or a curtain.

Porous surface: a surface with tiny holes (pores) that let water, oil and dirt soak in, for example bare cement or unsealed wood. Non-porous surface: a surface that liquids cannot enter, for example glass, glazed tiles and stainless steel.

Finish (seal): a coat such as varnish, wax, gloss paint or glaze that covers a porous material and makes its surface non-porous, as long as the coat is unbroken.

Hard and soft, porous and non-porous

Every surface in a home can be sorted twice. First ask: is it hard or soft? Then, for a hard surface, ask: does water stay on top, or soak in? Figure 1 shows the result.

The second question matters because dirt follows water. On a non-porous surface, dirt and germs sit on top, so a damp cloth and a little detergent remove them and the surface dries in minutes. On a porous surface, spills soak in and leave stains; too much water swells wood, loosens tiles and grows mould; and germs can hide in the pores. Porous surfaces need less water, faster drying and often a protective finish.

The water-drop test

When you are not sure whether a surface is sealed, put one drop of clean water on a hidden spot and watch for a minute.

The drop stays round and shiny: the surface is sealed (non-porous). It can be damp-wiped.
The drop spreads and the spot turns darker: the surface is porous. Use a barely damp cloth and dry it at once, or clean it dry.

Hard surfaces in a Rwandan home

Surface	Where you find it	What it is like	How to clean it	Never
Cement (concrete) floor	sitting rooms, verandas, stores	hard-wearing; porous unless painted or polished	sweep, then mop with detergent water; dry well	leave pools of water or grease to soak in
Glazed ceramic tiles	bathrooms, kitchens, floors	tiles are non-porous; the cement grout between them is porous	wipe or mop; scrub grout with a small brush	use strong acid on the grout, which dissolves it
Terrazzo and marble	floors and stairs of offices and newer homes	marble chips in cement, polished; damaged by acids	sweep, then mop with neutral detergent	use vinegar or lemon juice, which eat into the shine
Varnished or painted wood	tables, doors, cupboards	non-porous while the finish is unbroken	dust, then wipe with a cloth wrung almost dry	leave hot or wet items on it (white rings)
Unsealed wood	chopping boards, stools, shelves	porous; swells and cracks when soaked	scrub along the grain with soapy water, rinse, stand on edge to dry	soak it or leave it wet
Glass and mirrors	windows, cupboard doors	non-porous and easily scratched	wipe with a damp cloth, then polish dry with paper or a lint-free cloth	use sand, ash or scouring powder
Stainless steel and aluminium	sinks, pans, taps	non-porous; aluminium darkens with strong alkalis	wash with detergent, rinse, dry to stop water spots	leave bleach standing on it: chlorine pits the metal, so rinse after disinfecting
Painted walls	every room	gloss paint is washable; matt (emulsion) paint is more porous	dust; wipe marks gently from the bottom up	scrub matt paint hard: it rubs off
Earth (mud) floors and walls	traditional and rural houses	very porous and soft; damaged by water	sweep gently with a soft broom; repair worn patches with fresh plaster	wash with water

Soft surfaces

Soft surfaces are made of fibres, so dirt does not lie on them; it settles between the fibres. A wet cloth only pushes it deeper. Soft surfaces are cleaned by lifting the dirt out: shaking, beating, brushing or vacuuming. Water is used only when the fabric allows it and when it can dry completely, ideally in sunlight and moving air.

Soft surface	Usual cleaning	Point to watch
Carpets and rugs	vacuum or brush often; beat small rugs outside; blot spills at once	rub a spill and it spreads; blot from the outside of the stain inwards
Woven mats (ikirago, sisal, papyrus)	shake outside; air in the sun; wipe with a damp cloth only if needed	never soak them: plant fibres rot and grow mould
Upholstery (sofa and chair covers)	brush or vacuum; spot-clean; wash removable covers	test any cleaner on a hidden part first
Curtains and blinds	shake or vacuum; wash as the care label says	take down hooks and rings before washing
Mattresses, pillows, blankets	air in the sun; turn the mattress; wash covers	a damp mattress grows mould and attracts bed bugs

Worked example

Worked example 1: one spill, two floors. Orange juice is spilled on a glazed-tile kitchen floor and on a terrazzo corridor. A cousin suggests lemon juice to remove the sticky mark from both. Is this a good idea?

Identify the surfaces. Glazed tiles are non-porous; terrazzo is porous and contains marble chips.
Recall what attacks each. Marble is calcium carbonate, which reacts with acids. Lemon juice and orange juice are both acids.
Decide. On the tiles, the acid does no harm, but plain water with a little detergent is enough. On the terrazzo, both juices must be wiped up quickly, and lemon juice must never be added, because acid dulls and pits the polish.
Answer: wipe both spills at once with a damp cloth and neutral detergent; keep acids off terrazzo and marble.

Worked example

Worked example 2: classify a bedroom. A bedroom has a painted wooden door, a glass window, a cement floor, a sisal mat, cotton curtains, a foam mattress and a varnished stool. Sort them.

Soft surfaces (fibres or padding): sisal mat, cotton curtains, foam mattress.
Hard and non-porous (sealed): glass window, painted door, varnished stool.
Hard and porous: cement floor (unless painted or polished).
Consequence for cleaning: the mat, curtains and mattress are shaken, brushed or aired; the window, door and stool are damp-wiped; the floor is swept, then mopped and dried quickly.

Warning

Common mistakes. Using one wet cloth for everything; scrubbing glass, plastic or non-stick pans with sand or scouring powder (they scratch, and dirt then lodges in the scratches); putting vinegar or lemon on marble, terrazzo or tile grout; and leaving soft surfaces damp. Before using any new product on a surface, test it on a small hidden spot.

Tip

Memory hook: "Wipe the hard, lift the soft, and keep the porous dry." Ask two questions of every surface: is it hard or soft, and does water stay on top or soak in?

✦

Practice

Define a porous surface and give two examples from a kitchen.
Sort these into hard or soft surfaces: curtain, terrazzo, mattress, mirror, sofa cover, aluminium pan.
Describe the water-drop test and what each result tells you.
Explain why a damp cloth cleans a glazed tile well but does a poor job on a carpet.
Kalisa wants to remove limescale with vinegar from a terrazzo floor around a tap. Advise him, giving a reason.
A woven mat has been left on a wet veranda floor for a week. Predict two problems and suggest how to prevent them.
A family can afford to seal only one surface this year: the bare wooden worktop where they prepare food, or the varnished table in the sitting room, which is already in good condition. Which should they seal? Justify your choice.

Show answersHide answers

A surface with tiny holes that let liquids and dirt soak in; for example unsealed wooden chopping board, bare cement floor, tile grout.
Hard: terrazzo, mirror, aluminium pan. Soft: curtain, mattress, sofa cover.
Put a drop of water on a hidden spot for a minute. If it stays round and shiny, the surface is sealed and can be damp-wiped; if it spreads and darkens the spot, it is porous and needs little water and fast drying.
The tile is non-porous, so dirt sits on top and is wiped away. On a carpet, dirt settles between the fibres; the wet cloth pushes it deeper, so it must be lifted out by vacuuming or brushing.
He should not. Vinegar is an acid, and terrazzo contains marble chips that acids dissolve, leaving a dull, pitted patch. He should wipe the area with neutral detergent and dry it after each use of the tap.
The plant fibres will rot and grow mould, and the mat will smell and may stain the floor. Prevent it by lifting the mat, drying it in the sun and keeping it on a dry floor.
The bare wooden worktop. It is porous, so food juices and germs soak into it where food is prepared, and water makes it swell and crack. The table is already sealed, so sealing it again adds little.

Sources and credits

Lesson text, tables, Figure 1, worked examples and practice: written by Ganzaa.
Photo: Ikirago (Umusambi), Igiraneza Divine, Wikimedia Commons, CC BY-SA 4.0.

1Hard and soft, porous and non-porous

2The water-drop test

3Hard surfaces in a Rwandan home

4Soft surfaces

Hard and soft, porous and non-porous

The water-drop test

Hard surfaces in a Rwandan home

Soft surfaces