This paper presents strength, stiffness, and porosity characteristics of commercially available cold-curing epoxy adhesives for structural engineering applications in the field of externally bonded and/or near-surface mounted composite strip reinforcements. Depending on specific requirements, accelerated curing of the adhesive under high temperatures might be necessary. Experimental investigations aimed at assessing the possible differences in strength and stiffness between samples cured at elevated temperatures for a defined time span and the ones cured at room temperature. It could be demonstrated that for the same specimen age, nominal tensile strength and stiffness are lower after an initial accelerated curing process at elevated temperatures. Furthermore, it could be shown that the specimens after an accelerated curing at elevated temperatures exhibited an increased porosity. The development of a numerical code for image analysis allowed a detailed inspection of several fracture surfaces and subsequently to assess the level of decrease in available cross-section due to an increased overall porosity. Cross-section area losses in the range of 10–15% compared to the reference specimens could be deduced. The subsequent derivation of the actual tensile strength exhibits smaller differences between the room and high temperature exposed specimens while curing. Regardless of the short-term material strength, the observed porosity might be subject of important durability issues on a long-term and needs further investigation.FEDER funds through the Operational Program for Competitiveness Factors - COMPETE and National Funds through FCT - Portuguese Foundation for Science and Technology under the projects FRPreDur FCOMP- 01-0124-FEDER-028865 (FCT no. PTDC/ECM-EST/2424/2012)The authors want to express their gratitude to Max Heusser and Milos Dimic (Empa, CH) for their assistance in the experimental investigation. Marcel Rees, Iurii Burda and Andrea Battisti (Empa, CH) are kindly acknowledged for their assistance with the vacuum mixer and the sample preparation for porosity assessment. Eventually, Esther Strub (Empa, CH) is acknowledged for the instructions about the miscroscope utilization. Distributors S&P Clever Reinforcement AG (CH) and Sika (CH) are also acknowledged for their material provision. This work is also supported by FEDER funds through the Operational Program for Competitiveness Factors - COMPETE and National Funds through FCT - Portuguese Foundation for Science and Technology under the projects FRPreDur FCOMP- 01-0124-FEDER-028865 (FCT no. PTDC/ECM-EST/2424/2012)