In an attempt to summarize this simply and usefully, I have divided the properties into historical time periods that are linked to construction eras in terms of change in construction styles/methods. Listed below are property maintenance needs and potential defects that may be present when you first investigate a property purchase. A full inspection should be done prior to purchase to make corrections in advance or, alternatively, to plan for accounting for pending costs of repairs.

Georgian/Regency Period – 1714-1837 and Victorian/Edwardian Period – 1837-1914

During this 200-year period, a variety of different building styles and floor designs were introduced. Despite that, the actual construction methods used did not vary much, so the type of defects and maintenance needs are common.

Areas of concern include:

arc failure – Where brick or stone arches have been built over exterior door and window openings while timber-backed lintels are used on the inner side of the arch. Usually the outer side of the arch fails, leaving only the inner lintel to bear all the weight, which then hastens the failure of the timber lintel.

Joint failure between adjoining walls – This particularly affects the Georgian period, where the front walls of the building were finished last to make it easier for builders to access. The joints are considered to be inadequate or fail to make any physical connection and allow lateral movement at the joint between the external walls. Beware of broken headers.

Defective lime mortar – In this period, lime mortar was regularly used on bricks and masonry, but the problem is that it will break down over time in more acidic atmospheres, such as cities and urban areas. This means a higher chance of needing to re-target with modern mortar.

drainage problems – During the 19th century, the underground drainage channels were carried out by means of salt glazing. These pipes are now approaching 150 years old on average and will have developed both cracks and porous joints. For above ground drainage, these pipes are made of iron and generally show significant corrosion on the wall facing side of the pipe.

Improper use of cement as replacement mortar – Cement is used because it is strong and dense, yet it is also prone to cracking and does not expand or contract. The grouting of a wall previously plastered with lime mortar can cause the brick to break on the face. Also, because cement is denser than lime mortar, it can prevent a wall from letting moisture escape as the original design intended.

inadequate foundation – Some of the older houses from this period, especially those in the lower price range of the market, had no foundations or very shallow foundations. This can lead to quite serious subsidence and collapse in some cases, a surveyor should be able to help you here.

Missing the moisture-proof race – Both Georgian and Regency houses were rarely built with damp proof courses. This will increase the chances of rising damp.

overloaded wood floors – Compared to today’s modern joists, joists are often undersized for the job, especially on upper floors. This often results in excessive floor movement and is compounded by the more substantial level of furniture we expect today.

penetrating damp – Beam and joist ends were incorporated as standard into solid exterior walls approximately half a brick deep. However, when the external wall is <=225mm, the amount of solid protection from the outside is not sufficient and moisture can penetrate and rot the timbers.

Poor quality materials. – Spot purchases by “thrifty” builders result in sub-standard materials being used. It applies particularly to leased property where the builder’s game plan was to build to a quality sufficient to last the lease term, say 45, 50 or 99 years.

Poorly ventilated wooden ground floors – Inadequate number of air bricks to ventilate suspended wood sub-floors can cause unventilated portions that are at increased risk of moisture and mold growth. This can be made worse when the void below the floor is blocked by builder’s debris.

roof covers – Rotten deck slats and nail breakage due to rust is a frequent problem on both tile and slate roofs. Slate roofs should also be inspected for any signs of sloughing due to prolonged fort setting. More in Wales than England due to the softer variant of the slates found in Wales.

ceiling beams – Frequently it can be affected by wet rot due to not having used felt or due to failures in the gutters.

windows – Windows made of wood usually suffer a particular degree of humidity on the sills. This is due to age and a lack of regular protective maintenance. Metal windows also deteriorate in a similar way due to rust.

worm attack – Softwoods are likely to be affected to some extent by woodworms.

Pre-WWII housing – 1918-1939

In this period, house construction was generally of a high quality due to the further introduction of statutes which then encouraged the drive for standardization in both design and construction. It has also learned from many of the construction and material choice mistakes of the past.

However, here are the areas to watch:

Failure of cavity wall union – Houses with cavity walls suffer from wall tie failure due to rust. This could happen because the wall ties are not sufficiently protected or if they were galvanized then that protection has also worn away over time.

Condensation – In 1930s townhouses of this era, condensation is a common problem in bathrooms. The reason for this is that in these designs, the bathroom is usually located in the back corner of the house with two sides of the room as external walls. The recommendation is to adapt the cavity with thermal insulation.

rising damp – The wet layer of bituminous felt can show brittleness and cracks that allow water to pass through. Where the floors are concrete (not so common in this period) full waterproofing may be lacking.

rusty metal windows – Caused by lack of galvanization and oxidation. Moisture is often the source of rust due to condensation caused by cold single-pane windows that let a lot of heat escape.

Postwar housing – 1945-1990

Fewer obvious defects to pay attention to due to material advancement and less time to watch problems occur.

failure of wall ties – Due to ineffective long-term rust protection or lack of rust protection

Sulfate attack on soils – This occurs when the hard material used to build the floor contains sulfates and when the waterproof membrane is deficient or missing.

Cracks in the concrete floor – In previous concrete floors this is caused by unconsolidated hard core

rising damp – On the first concrete floors caused by the lack of a moisture-proof membrane

lack of rigidity – Observed on upper floors in 1950s construction and generally undersized floors as a result of material shortages

fungus attack – Impacts on exterior carpentry (doors and windows) caused by poor quality wood.

In short, the number and variety of repair and maintenance issues is greater with the age of the property. This may seem like an obvious statement, but it’s not just age that plays it apart, it’s also about understanding migration in terms of building materials and understanding design that has improved over time. This is a natural evolutionary process and today’s newer homes continue to improve in terms of construction material innovation. This article is not intended to deter the investor from older properties. The objective is to make the investor aware of the potential problems in terms of repair and maintenance that should be expected with a property of a certain age. With that understood, older properties can make fantastic investments with high rental appeal, potential for capital growth and, in many cases, a great location due to their age as the area has expanded around them. High quality property management or rental agents should also be able to assess any potential investment property with the above in mind and give good advice based on your local area.